osdep.c: Fix accept4 fallback
[qemu.git] / qemu-options.hx
blobe2edd71901befa4ccae2c89458819ecdf7d00486
1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help) is used to construct
5 HXCOMM option structures, enums and help message.
6 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
8 DEFHEADING(Standard options:)
9 STEXI
10 @table @option
11 ETEXI
13 DEF("help", 0, QEMU_OPTION_h,
14 "-h or -help display this help and exit\n")
15 STEXI
16 @item -h
17 Display help and exit
18 ETEXI
20 DEF("version", 0, QEMU_OPTION_version,
21 "-version display version information and exit\n")
22 STEXI
23 @item -version
24 Display version information and exit
25 ETEXI
27 DEF("M", HAS_ARG, QEMU_OPTION_M,
28 "-M machine select emulated machine (-M ? for list)\n")
29 STEXI
30 @item -M @var{machine}
31 Select the emulated @var{machine} (@code{-M ?} for list)
32 ETEXI
34 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
35 "-cpu cpu select CPU (-cpu ? for list)\n")
36 STEXI
37 @item -cpu @var{model}
38 Select CPU model (-cpu ? for list and additional feature selection)
39 ETEXI
41 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
42 "-smp n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
43 " set the number of CPUs to 'n' [default=1]\n"
44 " maxcpus= maximum number of total cpus, including\n"
45 " offline CPUs for hotplug, etc\n"
46 " cores= number of CPU cores on one socket\n"
47 " threads= number of threads on one CPU core\n"
48 " sockets= number of discrete sockets in the system\n")
49 STEXI
50 @item -smp @var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
51 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
52 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
53 to 4.
54 For the PC target, the number of @var{cores} per socket, the number
55 of @var{threads} per cores and the total number of @var{sockets} can be
56 specified. Missing values will be computed. If any on the three values is
57 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
58 specifies the maximum number of hotpluggable CPUs.
59 ETEXI
61 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
62 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n")
63 STEXI
64 @item -numa @var{opts}
65 Simulate a multi node NUMA system. If mem and cpus are omitted, resources
66 are split equally.
67 ETEXI
69 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
70 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n")
71 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "")
72 STEXI
73 @item -fda @var{file}
74 @item -fdb @var{file}
75 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
76 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
77 ETEXI
79 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
80 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n")
81 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "")
82 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
83 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n")
84 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "")
85 STEXI
86 @item -hda @var{file}
87 @item -hdb @var{file}
88 @item -hdc @var{file}
89 @item -hdd @var{file}
90 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
91 ETEXI
93 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
94 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n")
95 STEXI
96 @item -cdrom @var{file}
97 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
98 @option{-cdrom} at the same time). You can use the host CD-ROM by
99 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
100 ETEXI
102 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
103 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
104 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
105 " [,cache=writethrough|writeback|none][,format=f][,serial=s]\n"
106 " [,addr=A][,id=name][,aio=threads|native]\n"
107 " use 'file' as a drive image\n")
108 DEF("set", HAS_ARG, QEMU_OPTION_set,
109 "-set group.id.arg=value\n"
110 " set <arg> parameter for item <id> of type <group>\n"
111 " i.e. -set drive.$id.file=/path/to/image\n")
112 DEF("global", HAS_ARG, QEMU_OPTION_global,
113 "-global driver.property=value\n"
114 " set a global default for a driver property\n")
115 STEXI
116 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
118 Define a new drive. Valid options are:
120 @table @option
121 @item file=@var{file}
122 This option defines which disk image (@pxref{disk_images}) to use with
123 this drive. If the filename contains comma, you must double it
124 (for instance, "file=my,,file" to use file "my,file").
125 @item if=@var{interface}
126 This option defines on which type on interface the drive is connected.
127 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
128 @item bus=@var{bus},unit=@var{unit}
129 These options define where is connected the drive by defining the bus number and
130 the unit id.
131 @item index=@var{index}
132 This option defines where is connected the drive by using an index in the list
133 of available connectors of a given interface type.
134 @item media=@var{media}
135 This option defines the type of the media: disk or cdrom.
136 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
137 These options have the same definition as they have in @option{-hdachs}.
138 @item snapshot=@var{snapshot}
139 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
140 @item cache=@var{cache}
141 @var{cache} is "none", "writeback", or "writethrough" and controls how the host cache is used to access block data.
142 @item aio=@var{aio}
143 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
144 @item format=@var{format}
145 Specify which disk @var{format} will be used rather than detecting
146 the format. Can be used to specifiy format=raw to avoid interpreting
147 an untrusted format header.
148 @item serial=@var{serial}
149 This option specifies the serial number to assign to the device.
150 @item addr=@var{addr}
151 Specify the controller's PCI address (if=virtio only).
152 @end table
154 By default, writethrough caching is used for all block device. This means that
155 the host page cache will be used to read and write data but write notification
156 will be sent to the guest only when the data has been reported as written by
157 the storage subsystem.
159 Writeback caching will report data writes as completed as soon as the data is
160 present in the host page cache. This is safe as long as you trust your host.
161 If your host crashes or loses power, then the guest may experience data
162 corruption. When using the @option{-snapshot} option, writeback caching is
163 used by default.
165 The host page cache can be avoided entirely with @option{cache=none}. This will
166 attempt to do disk IO directly to the guests memory. QEMU may still perform
167 an internal copy of the data.
169 Some block drivers perform badly with @option{cache=writethrough}, most notably,
170 qcow2. If performance is more important than correctness,
171 @option{cache=writeback} should be used with qcow2.
173 Instead of @option{-cdrom} you can use:
174 @example
175 qemu -drive file=file,index=2,media=cdrom
176 @end example
178 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
179 use:
180 @example
181 qemu -drive file=file,index=0,media=disk
182 qemu -drive file=file,index=1,media=disk
183 qemu -drive file=file,index=2,media=disk
184 qemu -drive file=file,index=3,media=disk
185 @end example
187 You can connect a CDROM to the slave of ide0:
188 @example
189 qemu -drive file=file,if=ide,index=1,media=cdrom
190 @end example
192 If you don't specify the "file=" argument, you define an empty drive:
193 @example
194 qemu -drive if=ide,index=1,media=cdrom
195 @end example
197 You can connect a SCSI disk with unit ID 6 on the bus #0:
198 @example
199 qemu -drive file=file,if=scsi,bus=0,unit=6
200 @end example
202 Instead of @option{-fda}, @option{-fdb}, you can use:
203 @example
204 qemu -drive file=file,index=0,if=floppy
205 qemu -drive file=file,index=1,if=floppy
206 @end example
208 By default, @var{interface} is "ide" and @var{index} is automatically
209 incremented:
210 @example
211 qemu -drive file=a -drive file=b"
212 @end example
213 is interpreted like:
214 @example
215 qemu -hda a -hdb b
216 @end example
217 ETEXI
219 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
220 "-mtdblock file use 'file' as on-board Flash memory image\n")
221 STEXI
223 @item -mtdblock @var{file}
224 Use @var{file} as on-board Flash memory image.
225 ETEXI
227 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
228 "-sd file use 'file' as SecureDigital card image\n")
229 STEXI
230 @item -sd @var{file}
231 Use @var{file} as SecureDigital card image.
232 ETEXI
234 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
235 "-pflash file use 'file' as a parallel flash image\n")
236 STEXI
237 @item -pflash @var{file}
238 Use @var{file} as a parallel flash image.
239 ETEXI
241 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
242 "-boot [order=drives][,once=drives][,menu=on|off]\n"
243 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n")
244 STEXI
245 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off]
247 Specify boot order @var{drives} as a string of drive letters. Valid
248 drive letters depend on the target achitecture. The x86 PC uses: a, b
249 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
250 from network adapter 1-4), hard disk boot is the default. To apply a
251 particular boot order only on the first startup, specify it via
252 @option{once}.
254 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
255 as firmware/BIOS supports them. The default is non-interactive boot.
257 @example
258 # try to boot from network first, then from hard disk
259 qemu -boot order=nc
260 # boot from CD-ROM first, switch back to default order after reboot
261 qemu -boot once=d
262 @end example
264 Note: The legacy format '-boot @var{drives}' is still supported but its
265 use is discouraged as it may be removed from future versions.
266 ETEXI
268 DEF("snapshot", 0, QEMU_OPTION_snapshot,
269 "-snapshot write to temporary files instead of disk image files\n")
270 STEXI
271 @item -snapshot
272 Write to temporary files instead of disk image files. In this case,
273 the raw disk image you use is not written back. You can however force
274 the write back by pressing @key{C-a s} (@pxref{disk_images}).
275 ETEXI
277 DEF("m", HAS_ARG, QEMU_OPTION_m,
278 "-m megs set virtual RAM size to megs MB [default=%d]\n")
279 STEXI
280 @item -m @var{megs}
281 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
282 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
283 gigabytes respectively.
284 ETEXI
286 DEF("k", HAS_ARG, QEMU_OPTION_k,
287 "-k language use keyboard layout (for example 'fr' for French)\n")
288 STEXI
289 @item -k @var{language}
291 Use keyboard layout @var{language} (for example @code{fr} for
292 French). This option is only needed where it is not easy to get raw PC
293 keycodes (e.g. on Macs, with some X11 servers or with a VNC
294 display). You don't normally need to use it on PC/Linux or PC/Windows
295 hosts.
297 The available layouts are:
298 @example
299 ar de-ch es fo fr-ca hu ja mk no pt-br sv
300 da en-gb et fr fr-ch is lt nl pl ru th
301 de en-us fi fr-be hr it lv nl-be pt sl tr
302 @end example
304 The default is @code{en-us}.
305 ETEXI
308 #ifdef HAS_AUDIO
309 DEF("audio-help", 0, QEMU_OPTION_audio_help,
310 "-audio-help print list of audio drivers and their options\n")
311 #endif
312 STEXI
313 @item -audio-help
315 Will show the audio subsystem help: list of drivers, tunable
316 parameters.
317 ETEXI
319 #ifdef HAS_AUDIO
320 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
321 "-soundhw c1,... enable audio support\n"
322 " and only specified sound cards (comma separated list)\n"
323 " use -soundhw ? to get the list of supported cards\n"
324 " use -soundhw all to enable all of them\n")
325 #endif
326 STEXI
327 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
329 Enable audio and selected sound hardware. Use ? to print all
330 available sound hardware.
332 @example
333 qemu -soundhw sb16,adlib disk.img
334 qemu -soundhw es1370 disk.img
335 qemu -soundhw ac97 disk.img
336 qemu -soundhw all disk.img
337 qemu -soundhw ?
338 @end example
340 Note that Linux's i810_audio OSS kernel (for AC97) module might
341 require manually specifying clocking.
343 @example
344 modprobe i810_audio clocking=48000
345 @end example
346 ETEXI
348 STEXI
349 @end table
350 ETEXI
352 DEF("usb", 0, QEMU_OPTION_usb,
353 "-usb enable the USB driver (will be the default soon)\n")
354 STEXI
355 USB options:
356 @table @option
358 @item -usb
359 Enable the USB driver (will be the default soon)
360 ETEXI
362 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
363 "-usbdevice name add the host or guest USB device 'name'\n")
364 STEXI
366 @item -usbdevice @var{devname}
367 Add the USB device @var{devname}. @xref{usb_devices}.
369 @table @option
371 @item mouse
372 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
374 @item tablet
375 Pointer device that uses absolute coordinates (like a touchscreen). This
376 means qemu is able to report the mouse position without having to grab the
377 mouse. Also overrides the PS/2 mouse emulation when activated.
379 @item disk:[format=@var{format}]:@var{file}
380 Mass storage device based on file. The optional @var{format} argument
381 will be used rather than detecting the format. Can be used to specifiy
382 @code{format=raw} to avoid interpreting an untrusted format header.
384 @item host:@var{bus}.@var{addr}
385 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
387 @item host:@var{vendor_id}:@var{product_id}
388 Pass through the host device identified by @var{vendor_id}:@var{product_id}
389 (Linux only).
391 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
392 Serial converter to host character device @var{dev}, see @code{-serial} for the
393 available devices.
395 @item braille
396 Braille device. This will use BrlAPI to display the braille output on a real
397 or fake device.
399 @item net:@var{options}
400 Network adapter that supports CDC ethernet and RNDIS protocols.
402 @end table
403 ETEXI
405 DEF("device", HAS_ARG, QEMU_OPTION_device,
406 "-device driver[,options] add device\n")
407 DEF("name", HAS_ARG, QEMU_OPTION_name,
408 "-name string1[,process=string2]\n"
409 " set the name of the guest\n"
410 " string1 sets the window title and string2 the process name (on Linux)\n")
411 STEXI
412 @item -name @var{name}
413 Sets the @var{name} of the guest.
414 This name will be displayed in the SDL window caption.
415 The @var{name} will also be used for the VNC server.
416 Also optionally set the top visible process name in Linux.
417 ETEXI
419 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
420 "-uuid %%08x-%%04x-%%04x-%%04x-%%012x\n"
421 " specify machine UUID\n")
422 STEXI
423 @item -uuid @var{uuid}
424 Set system UUID.
425 ETEXI
427 STEXI
428 @end table
429 ETEXI
431 DEFHEADING()
433 DEFHEADING(Display options:)
435 STEXI
436 @table @option
437 ETEXI
439 DEF("nographic", 0, QEMU_OPTION_nographic,
440 "-nographic disable graphical output and redirect serial I/Os to console\n")
441 STEXI
442 @item -nographic
444 Normally, QEMU uses SDL to display the VGA output. With this option,
445 you can totally disable graphical output so that QEMU is a simple
446 command line application. The emulated serial port is redirected on
447 the console. Therefore, you can still use QEMU to debug a Linux kernel
448 with a serial console.
449 ETEXI
451 #ifdef CONFIG_CURSES
452 DEF("curses", 0, QEMU_OPTION_curses,
453 "-curses use a curses/ncurses interface instead of SDL\n")
454 #endif
455 STEXI
456 @item -curses
458 Normally, QEMU uses SDL to display the VGA output. With this option,
459 QEMU can display the VGA output when in text mode using a
460 curses/ncurses interface. Nothing is displayed in graphical mode.
461 ETEXI
463 #ifdef CONFIG_SDL
464 DEF("no-frame", 0, QEMU_OPTION_no_frame,
465 "-no-frame open SDL window without a frame and window decorations\n")
466 #endif
467 STEXI
468 @item -no-frame
470 Do not use decorations for SDL windows and start them using the whole
471 available screen space. This makes the using QEMU in a dedicated desktop
472 workspace more convenient.
473 ETEXI
475 #ifdef CONFIG_SDL
476 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
477 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n")
478 #endif
479 STEXI
480 @item -alt-grab
482 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt).
483 ETEXI
485 #ifdef CONFIG_SDL
486 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
487 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n")
488 #endif
489 STEXI
490 @item -ctrl-grab
492 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt).
493 ETEXI
495 #ifdef CONFIG_SDL
496 DEF("no-quit", 0, QEMU_OPTION_no_quit,
497 "-no-quit disable SDL window close capability\n")
498 #endif
499 STEXI
500 @item -no-quit
502 Disable SDL window close capability.
503 ETEXI
505 #ifdef CONFIG_SDL
506 DEF("sdl", 0, QEMU_OPTION_sdl,
507 "-sdl enable SDL\n")
508 #endif
509 STEXI
510 @item -sdl
512 Enable SDL.
513 ETEXI
515 DEF("portrait", 0, QEMU_OPTION_portrait,
516 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n")
517 STEXI
518 @item -portrait
520 Rotate graphical output 90 deg left (only PXA LCD).
521 ETEXI
523 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
524 "-vga [std|cirrus|vmware|xenfb|none]\n"
525 " select video card type\n")
526 STEXI
527 @item -vga @var{type}
528 Select type of VGA card to emulate. Valid values for @var{type} are
529 @table @option
530 @item cirrus
531 Cirrus Logic GD5446 Video card. All Windows versions starting from
532 Windows 95 should recognize and use this graphic card. For optimal
533 performances, use 16 bit color depth in the guest and the host OS.
534 (This one is the default)
535 @item std
536 Standard VGA card with Bochs VBE extensions. If your guest OS
537 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
538 to use high resolution modes (>= 1280x1024x16) then you should use
539 this option.
540 @item vmware
541 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
542 recent XFree86/XOrg server or Windows guest with a driver for this
543 card.
544 @item none
545 Disable VGA card.
546 @end table
547 ETEXI
549 DEF("full-screen", 0, QEMU_OPTION_full_screen,
550 "-full-screen start in full screen\n")
551 STEXI
552 @item -full-screen
553 Start in full screen.
554 ETEXI
556 #if defined(TARGET_PPC) || defined(TARGET_SPARC)
557 DEF("g", 1, QEMU_OPTION_g ,
558 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n")
559 #endif
560 STEXI
561 ETEXI
563 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
564 "-vnc display start a VNC server on display\n")
565 STEXI
566 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
568 Normally, QEMU uses SDL to display the VGA output. With this option,
569 you can have QEMU listen on VNC display @var{display} and redirect the VGA
570 display over the VNC session. It is very useful to enable the usb
571 tablet device when using this option (option @option{-usbdevice
572 tablet}). When using the VNC display, you must use the @option{-k}
573 parameter to set the keyboard layout if you are not using en-us. Valid
574 syntax for the @var{display} is
576 @table @option
578 @item @var{host}:@var{d}
580 TCP connections will only be allowed from @var{host} on display @var{d}.
581 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
582 be omitted in which case the server will accept connections from any host.
584 @item unix:@var{path}
586 Connections will be allowed over UNIX domain sockets where @var{path} is the
587 location of a unix socket to listen for connections on.
589 @item none
591 VNC is initialized but not started. The monitor @code{change} command
592 can be used to later start the VNC server.
594 @end table
596 Following the @var{display} value there may be one or more @var{option} flags
597 separated by commas. Valid options are
599 @table @option
601 @item reverse
603 Connect to a listening VNC client via a ``reverse'' connection. The
604 client is specified by the @var{display}. For reverse network
605 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
606 is a TCP port number, not a display number.
608 @item password
610 Require that password based authentication is used for client connections.
611 The password must be set separately using the @code{change} command in the
612 @ref{pcsys_monitor}
614 @item tls
616 Require that client use TLS when communicating with the VNC server. This
617 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
618 attack. It is recommended that this option be combined with either the
619 @option{x509} or @option{x509verify} options.
621 @item x509=@var{/path/to/certificate/dir}
623 Valid if @option{tls} is specified. Require that x509 credentials are used
624 for negotiating the TLS session. The server will send its x509 certificate
625 to the client. It is recommended that a password be set on the VNC server
626 to provide authentication of the client when this is used. The path following
627 this option specifies where the x509 certificates are to be loaded from.
628 See the @ref{vnc_security} section for details on generating certificates.
630 @item x509verify=@var{/path/to/certificate/dir}
632 Valid if @option{tls} is specified. Require that x509 credentials are used
633 for negotiating the TLS session. The server will send its x509 certificate
634 to the client, and request that the client send its own x509 certificate.
635 The server will validate the client's certificate against the CA certificate,
636 and reject clients when validation fails. If the certificate authority is
637 trusted, this is a sufficient authentication mechanism. You may still wish
638 to set a password on the VNC server as a second authentication layer. The
639 path following this option specifies where the x509 certificates are to
640 be loaded from. See the @ref{vnc_security} section for details on generating
641 certificates.
643 @item sasl
645 Require that the client use SASL to authenticate with the VNC server.
646 The exact choice of authentication method used is controlled from the
647 system / user's SASL configuration file for the 'qemu' service. This
648 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
649 unprivileged user, an environment variable SASL_CONF_PATH can be used
650 to make it search alternate locations for the service config.
651 While some SASL auth methods can also provide data encryption (eg GSSAPI),
652 it is recommended that SASL always be combined with the 'tls' and
653 'x509' settings to enable use of SSL and server certificates. This
654 ensures a data encryption preventing compromise of authentication
655 credentials. See the @ref{vnc_security} section for details on using
656 SASL authentication.
658 @item acl
660 Turn on access control lists for checking of the x509 client certificate
661 and SASL party. For x509 certs, the ACL check is made against the
662 certificate's distinguished name. This is something that looks like
663 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
664 made against the username, which depending on the SASL plugin, may
665 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
666 When the @option{acl} flag is set, the initial access list will be
667 empty, with a @code{deny} policy. Thus no one will be allowed to
668 use the VNC server until the ACLs have been loaded. This can be
669 achieved using the @code{acl} monitor command.
671 @end table
672 ETEXI
674 STEXI
675 @end table
676 ETEXI
678 DEFHEADING()
680 #ifdef TARGET_I386
681 DEFHEADING(i386 target only:)
682 #endif
683 STEXI
684 @table @option
685 ETEXI
687 #ifdef TARGET_I386
688 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
689 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n")
690 #endif
691 STEXI
692 @item -win2k-hack
693 Use it when installing Windows 2000 to avoid a disk full bug. After
694 Windows 2000 is installed, you no longer need this option (this option
695 slows down the IDE transfers).
696 ETEXI
698 #ifdef TARGET_I386
699 HXCOMM Deprecated by -rtc
700 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "")
701 #endif
703 #ifdef TARGET_I386
704 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
705 "-no-fd-bootchk disable boot signature checking for floppy disks\n")
706 #endif
707 STEXI
708 @item -no-fd-bootchk
709 Disable boot signature checking for floppy disks in Bochs BIOS. It may
710 be needed to boot from old floppy disks.
711 ETEXI
713 #ifdef TARGET_I386
714 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
715 "-no-acpi disable ACPI\n")
716 #endif
717 STEXI
718 @item -no-acpi
719 Disable ACPI (Advanced Configuration and Power Interface) support. Use
720 it if your guest OS complains about ACPI problems (PC target machine
721 only).
722 ETEXI
724 #ifdef TARGET_I386
725 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
726 "-no-hpet disable HPET\n")
727 #endif
728 STEXI
729 @item -no-hpet
730 Disable HPET support.
731 ETEXI
733 #ifdef TARGET_I386
734 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
735 "-balloon none disable balloon device\n"
736 "-balloon virtio[,addr=str]\n"
737 " enable virtio balloon device (default)\n")
738 #endif
739 STEXI
740 @item -balloon none
741 Disable balloon device.
742 @item -balloon virtio[,addr=@var{addr}]
743 Enable virtio balloon device (default), optionally with PCI address
744 @var{addr}.
745 ETEXI
747 #ifdef TARGET_I386
748 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
749 "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,data=file1[:file2]...]\n"
750 " ACPI table description\n")
751 #endif
752 STEXI
753 @item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...]
754 Add ACPI table with specified header fields and context from specified files.
755 ETEXI
757 #ifdef TARGET_I386
758 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
759 "-smbios file=binary\n"
760 " load SMBIOS entry from binary file\n"
761 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%%d.%%d]\n"
762 " specify SMBIOS type 0 fields\n"
763 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
764 " [,uuid=uuid][,sku=str][,family=str]\n"
765 " specify SMBIOS type 1 fields\n")
766 #endif
767 STEXI
768 @item -smbios file=@var{binary}
769 Load SMBIOS entry from binary file.
771 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
772 Specify SMBIOS type 0 fields
774 @item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}][,family=@var{str}]
775 Specify SMBIOS type 1 fields
776 ETEXI
778 #ifdef TARGET_I386
779 DEFHEADING()
780 #endif
781 STEXI
782 @end table
783 ETEXI
785 DEFHEADING(Network options:)
786 STEXI
787 @table @option
788 ETEXI
790 HXCOMM Legacy slirp options (now moved to -net user):
791 #ifdef CONFIG_SLIRP
792 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "")
793 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "")
794 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "")
795 #ifndef _WIN32
796 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "")
797 #endif
798 #endif
800 DEF("net", HAS_ARG, QEMU_OPTION_net,
801 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
802 " create a new Network Interface Card and connect it to VLAN 'n'\n"
803 #ifdef CONFIG_SLIRP
804 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=y|n]\n"
805 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
806 " [,hostfwd=rule][,guestfwd=rule]"
807 #ifndef _WIN32
808 "[,smb=dir[,smbserver=addr]]\n"
809 #endif
810 " connect the user mode network stack to VLAN 'n', configure its\n"
811 " DHCP server and enabled optional services\n"
812 #endif
813 #ifdef _WIN32
814 "-net tap[,vlan=n][,name=str],ifname=name\n"
815 " connect the host TAP network interface to VLAN 'n'\n"
816 #else
817 "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off]\n"
818 " connect the host TAP network interface to VLAN 'n' and use the\n"
819 " network scripts 'file' (default=%s)\n"
820 " and 'dfile' (default=%s)\n"
821 " use '[down]script=no' to disable script execution\n"
822 " use 'fd=h' to connect to an already opened TAP interface\n"
823 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
824 " default of 'sndbuf=1048576' can be disabled using 'sndbuf=0')\n"
825 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
826 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
827 #endif
828 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
829 " connect the vlan 'n' to another VLAN using a socket connection\n"
830 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port]\n"
831 " connect the vlan 'n' to multicast maddr and port\n"
832 #ifdef CONFIG_VDE
833 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
834 " connect the vlan 'n' to port 'n' of a vde switch running\n"
835 " on host and listening for incoming connections on 'socketpath'.\n"
836 " Use group 'groupname' and mode 'octalmode' to change default\n"
837 " ownership and permissions for communication port.\n"
838 #endif
839 "-net dump[,vlan=n][,file=f][,len=n]\n"
840 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
841 "-net none use it alone to have zero network devices. If no -net option\n"
842 " is provided, the default is '-net nic -net user'\n")
843 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
844 "-netdev ["
845 #ifdef CONFIG_SLIRP
846 "user|"
847 #endif
848 "tap|"
849 #ifdef CONFIG_VDE
850 "vde|"
851 #endif
852 "socket],id=str[,option][,option][,...]\n")
853 STEXI
854 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}][,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
855 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
856 = 0 is the default). The NIC is an e1000 by default on the PC
857 target. Optionally, the MAC address can be changed to @var{mac}, the
858 device address set to @var{addr} (PCI cards only),
859 and a @var{name} can be assigned for use in monitor commands.
860 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
861 that the card should have; this option currently only affects virtio cards; set
862 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
863 NIC is created. Qemu can emulate several different models of network card.
864 Valid values for @var{type} are
865 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
866 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
867 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
868 Not all devices are supported on all targets. Use -net nic,model=?
869 for a list of available devices for your target.
871 @item -net user[,@var{option}][,@var{option}][,...]
872 Use the user mode network stack which requires no administrator
873 privilege to run. Valid options are:
875 @table @option
876 @item vlan=@var{n}
877 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
879 @item name=@var{name}
880 Assign symbolic name for use in monitor commands.
882 @item net=@var{addr}[/@var{mask}]
883 Set IP network address the guest will see. Optionally specify the netmask,
884 either in the form a.b.c.d or as number of valid top-most bits. Default is
885 10.0.2.0/8.
887 @item host=@var{addr}
888 Specify the guest-visible address of the host. Default is the 2nd IP in the
889 guest network, i.e. x.x.x.2.
891 @item restrict=y|yes|n|no
892 If this options is enabled, the guest will be isolated, i.e. it will not be
893 able to contact the host and no guest IP packets will be routed over the host
894 to the outside. This option does not affect explicitly set forwarding rule.
896 @item hostname=@var{name}
897 Specifies the client hostname reported by the builtin DHCP server.
899 @item dhcpstart=@var{addr}
900 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
901 is the 16th to 31st IP in the guest network, i.e. x.x.x.16 to x.x.x.31.
903 @item dns=@var{addr}
904 Specify the guest-visible address of the virtual nameserver. The address must
905 be different from the host address. Default is the 3rd IP in the guest network,
906 i.e. x.x.x.3.
908 @item tftp=@var{dir}
909 When using the user mode network stack, activate a built-in TFTP
910 server. The files in @var{dir} will be exposed as the root of a TFTP server.
911 The TFTP client on the guest must be configured in binary mode (use the command
912 @code{bin} of the Unix TFTP client).
914 @item bootfile=@var{file}
915 When using the user mode network stack, broadcast @var{file} as the BOOTP
916 filename. In conjunction with @option{tftp}, this can be used to network boot
917 a guest from a local directory.
919 Example (using pxelinux):
920 @example
921 qemu -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
922 @end example
924 @item smb=@var{dir}[,smbserver=@var{addr}]
925 When using the user mode network stack, activate a built-in SMB
926 server so that Windows OSes can access to the host files in @file{@var{dir}}
927 transparently. The IP address of the SMB server can be set to @var{addr}. By
928 default the 4th IP in the guest network is used, i.e. x.x.x.4.
930 In the guest Windows OS, the line:
931 @example
932 10.0.2.4 smbserver
933 @end example
934 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
935 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
937 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
939 Note that a SAMBA server must be installed on the host OS in
940 @file{/usr/sbin/smbd}. QEMU was tested successfully with smbd versions from
941 Red Hat 9, Fedora Core 3 and OpenSUSE 11.x.
943 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
944 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
945 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
946 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
947 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
948 be bound to a specific host interface. If no connection type is set, TCP is
949 used. This option can be given multiple times.
951 For example, to redirect host X11 connection from screen 1 to guest
952 screen 0, use the following:
954 @example
955 # on the host
956 qemu -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
957 # this host xterm should open in the guest X11 server
958 xterm -display :1
959 @end example
961 To redirect telnet connections from host port 5555 to telnet port on
962 the guest, use the following:
964 @example
965 # on the host
966 qemu -net user,hostfwd=tcp:5555::23 [...]
967 telnet localhost 5555
968 @end example
970 Then when you use on the host @code{telnet localhost 5555}, you
971 connect to the guest telnet server.
973 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
974 Forward guest TCP connections to the IP address @var{server} on port @var{port}
975 to the character device @var{dev}. This option can be given multiple times.
977 @end table
979 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
980 processed and applied to -net user. Mixing them with the new configuration
981 syntax gives undefined results. Their use for new applications is discouraged
982 as they will be removed from future versions.
984 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}]
985 Connect the host TAP network interface @var{name} to VLAN @var{n}, use
986 the network script @var{file} to configure it and the network script
987 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
988 automatically provides one. @option{fd}=@var{h} can be used to specify
989 the handle of an already opened host TAP interface. The default network
990 configure script is @file{/etc/qemu-ifup} and the default network
991 deconfigure script is @file{/etc/qemu-ifdown}. Use @option{script=no}
992 or @option{downscript=no} to disable script execution. Example:
994 @example
995 qemu linux.img -net nic -net tap
996 @end example
998 More complicated example (two NICs, each one connected to a TAP device)
999 @example
1000 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1001 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1002 @end example
1004 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1006 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1007 machine using a TCP socket connection. If @option{listen} is
1008 specified, QEMU waits for incoming connections on @var{port}
1009 (@var{host} is optional). @option{connect} is used to connect to
1010 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1011 specifies an already opened TCP socket.
1013 Example:
1014 @example
1015 # launch a first QEMU instance
1016 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1017 -net socket,listen=:1234
1018 # connect the VLAN 0 of this instance to the VLAN 0
1019 # of the first instance
1020 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1021 -net socket,connect=127.0.0.1:1234
1022 @end example
1024 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}]
1026 Create a VLAN @var{n} shared with another QEMU virtual
1027 machines using a UDP multicast socket, effectively making a bus for
1028 every QEMU with same multicast address @var{maddr} and @var{port}.
1029 NOTES:
1030 @enumerate
1031 @item
1032 Several QEMU can be running on different hosts and share same bus (assuming
1033 correct multicast setup for these hosts).
1034 @item
1035 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1036 @url{http://user-mode-linux.sf.net}.
1037 @item
1038 Use @option{fd=h} to specify an already opened UDP multicast socket.
1039 @end enumerate
1041 Example:
1042 @example
1043 # launch one QEMU instance
1044 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1045 -net socket,mcast=230.0.0.1:1234
1046 # launch another QEMU instance on same "bus"
1047 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1048 -net socket,mcast=230.0.0.1:1234
1049 # launch yet another QEMU instance on same "bus"
1050 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
1051 -net socket,mcast=230.0.0.1:1234
1052 @end example
1054 Example (User Mode Linux compat.):
1055 @example
1056 # launch QEMU instance (note mcast address selected
1057 # is UML's default)
1058 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1059 -net socket,mcast=239.192.168.1:1102
1060 # launch UML
1061 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1062 @end example
1064 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1065 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1066 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1067 and MODE @var{octalmode} to change default ownership and permissions for
1068 communication port. This option is available only if QEMU has been compiled
1069 with vde support enabled.
1071 Example:
1072 @example
1073 # launch vde switch
1074 vde_switch -F -sock /tmp/myswitch
1075 # launch QEMU instance
1076 qemu linux.img -net nic -net vde,sock=/tmp/myswitch
1077 @end example
1079 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1080 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1081 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1082 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1084 @item -net none
1085 Indicate that no network devices should be configured. It is used to
1086 override the default configuration (@option{-net nic -net user}) which
1087 is activated if no @option{-net} options are provided.
1089 @end table
1090 ETEXI
1092 DEFHEADING()
1094 DEFHEADING(Character device options:)
1096 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1097 "-chardev null,id=id\n"
1098 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1099 " [,server][,nowait][,telnet] (tcp)\n"
1100 "-chardev socket,id=id,path=path[,server][,nowait][,telnet] (unix)\n"
1101 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1102 " [,localport=localport][,ipv4][,ipv6]\n"
1103 "-chardev msmouse,id=id\n"
1104 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1105 "-chardev file,id=id,path=path\n"
1106 "-chardev pipe,id=id,path=path\n"
1107 #ifdef _WIN32
1108 "-chardev console,id=id\n"
1109 "-chardev serial,id=id,path=path\n"
1110 #else
1111 "-chardev pty,id=id\n"
1112 "-chardev stdio,id=id\n"
1113 #endif
1114 #ifdef CONFIG_BRLAPI
1115 "-chardev braille,id=id\n"
1116 #endif
1117 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1118 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1119 "-chardev tty,id=id,path=path\n"
1120 #endif
1121 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1122 "-chardev parport,id=id,path=path\n"
1123 #endif
1126 STEXI
1128 The general form of a character device option is:
1129 @table @option
1131 @item -chardev @var{backend} ,id=@var{id} [,@var{options}]
1133 Backend is one of:
1134 @option{null},
1135 @option{socket},
1136 @option{udp},
1137 @option{msmouse},
1138 @option{vc},
1139 @option{file},
1140 @option{pipe},
1141 @option{console},
1142 @option{serial},
1143 @option{pty},
1144 @option{stdio},
1145 @option{braille},
1146 @option{tty},
1147 @option{parport}.
1148 The specific backend will determine the applicable options.
1150 All devices must have an id, which can be any string up to 127 characters long.
1151 It is used to uniquely identify this device in other command line directives.
1153 Options to each backend are described below.
1155 @item -chardev null ,id=@var{id}
1156 A void device. This device will not emit any data, and will drop any data it
1157 receives. The null backend does not take any options.
1159 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1161 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1162 unix socket will be created if @option{path} is specified. Behaviour is
1163 undefined if TCP options are specified for a unix socket.
1165 @option{server} specifies that the socket shall be a listening socket.
1167 @option{nowait} specifies that QEMU should not block waiting for a client to
1168 connect to a listening socket.
1170 @option{telnet} specifies that traffic on the socket should interpret telnet
1171 escape sequences.
1173 TCP and unix socket options are given below:
1175 @table @option
1177 @item TCP options: port=@var{host} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1179 @option{host} for a listening socket specifies the local address to be bound.
1180 For a connecting socket species the remote host to connect to. @option{host} is
1181 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1183 @option{port} for a listening socket specifies the local port to be bound. For a
1184 connecting socket specifies the port on the remote host to connect to.
1185 @option{port} can be given as either a port number or a service name.
1186 @option{port} is required.
1188 @option{to} is only relevant to listening sockets. If it is specified, and
1189 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1190 to and including @option{to} until it succeeds. @option{to} must be specified
1191 as a port number.
1193 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1194 If neither is specified the socket may use either protocol.
1196 @option{nodelay} disables the Nagle algorithm.
1198 @item unix options: path=@var{path}
1200 @option{path} specifies the local path of the unix socket. @option{path} is
1201 required.
1203 @end table
1205 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1207 Sends all traffic from the guest to a remote host over UDP.
1209 @option{host} specifies the remote host to connect to. If not specified it
1210 defaults to @code{localhost}.
1212 @option{port} specifies the port on the remote host to connect to. @option{port}
1213 is required.
1215 @option{localaddr} specifies the local address to bind to. If not specified it
1216 defaults to @code{0.0.0.0}.
1218 @option{localport} specifies the local port to bind to. If not specified any
1219 available local port will be used.
1221 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1222 If neither is specified the device may use either protocol.
1224 @item -chardev msmouse ,id=@var{id}
1226 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1227 take any options.
1229 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1231 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1232 size.
1234 @option{width} and @option{height} specify the width and height respectively of
1235 the console, in pixels.
1237 @option{cols} and @option{rows} specify that the console be sized to fit a text
1238 console with the given dimensions.
1240 @item -chardev file ,id=@var{id} ,path=@var{path}
1242 Log all traffic received from the guest to a file.
1244 @option{path} specifies the path of the file to be opened. This file will be
1245 created if it does not already exist, and overwritten if it does. @option{path}
1246 is required.
1248 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1250 Create a two-way connection to the guest. The behaviour differs slightly between
1251 Windows hosts and other hosts:
1253 On Windows, a single duplex pipe will be created at
1254 @file{\\.pipe\@option{path}}.
1256 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1257 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1258 received by the guest. Data written by the guest can be read from
1259 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1260 be present.
1262 @option{path} forms part of the pipe path as described above. @option{path} is
1263 required.
1265 @item -chardev console ,id=@var{id}
1267 Send traffic from the guest to QEMU's standard output. @option{console} does not
1268 take any options.
1270 @option{console} is only available on Windows hosts.
1272 @item -chardev serial ,id=@var{id} ,path=@option{path}
1274 Send traffic from the guest to a serial device on the host.
1276 @option{serial} is
1277 only available on Windows hosts.
1279 @option{path} specifies the name of the serial device to open.
1281 @item -chardev pty ,id=@var{id}
1283 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1284 not take any options.
1286 @option{pty} is not available on Windows hosts.
1288 @item -chardev stdio ,id=@var{id}
1289 Connect to standard input and standard output of the qemu process.
1290 @option{stdio} does not take any options. @option{stdio} is not available on
1291 Windows hosts.
1293 @item -chardev braille ,id=@var{id}
1295 Connect to a local BrlAPI server. @option{braille} does not take any options.
1297 @item -chardev tty ,id=@var{id} ,path=@var{path}
1299 Connect to a local tty device.
1301 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1302 DragonFlyBSD hosts.
1304 @option{path} specifies the path to the tty. @option{path} is required.
1306 @item -chardev parport ,id=@var{id} ,path=@var{path}
1308 @option{parport} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1310 Connect to a local parallel port.
1312 @option{path} specifies the path to the parallel port device. @option{path} is
1313 required.
1315 @end table
1316 ETEXI
1318 DEFHEADING()
1320 DEFHEADING(Bluetooth(R) options:)
1322 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
1323 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
1324 "-bt hci,host[:id]\n" \
1325 " use host's HCI with the given name\n" \
1326 "-bt hci[,vlan=n]\n" \
1327 " emulate a standard HCI in virtual scatternet 'n'\n" \
1328 "-bt vhci[,vlan=n]\n" \
1329 " add host computer to virtual scatternet 'n' using VHCI\n" \
1330 "-bt device:dev[,vlan=n]\n" \
1331 " emulate a bluetooth device 'dev' in scatternet 'n'\n")
1332 STEXI
1333 @table @option
1335 @item -bt hci[...]
1336 Defines the function of the corresponding Bluetooth HCI. -bt options
1337 are matched with the HCIs present in the chosen machine type. For
1338 example when emulating a machine with only one HCI built into it, only
1339 the first @code{-bt hci[...]} option is valid and defines the HCI's
1340 logic. The Transport Layer is decided by the machine type. Currently
1341 the machines @code{n800} and @code{n810} have one HCI and all other
1342 machines have none.
1344 @anchor{bt-hcis}
1345 The following three types are recognized:
1347 @table @option
1348 @item -bt hci,null
1349 (default) The corresponding Bluetooth HCI assumes no internal logic
1350 and will not respond to any HCI commands or emit events.
1352 @item -bt hci,host[:@var{id}]
1353 (@code{bluez} only) The corresponding HCI passes commands / events
1354 to / from the physical HCI identified by the name @var{id} (default:
1355 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
1356 capable systems like Linux.
1358 @item -bt hci[,vlan=@var{n}]
1359 Add a virtual, standard HCI that will participate in the Bluetooth
1360 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
1361 VLANs, devices inside a bluetooth network @var{n} can only communicate
1362 with other devices in the same network (scatternet).
1363 @end table
1365 @item -bt vhci[,vlan=@var{n}]
1366 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
1367 to the host bluetooth stack instead of to the emulated target. This
1368 allows the host and target machines to participate in a common scatternet
1369 and communicate. Requires the Linux @code{vhci} driver installed. Can
1370 be used as following:
1372 @example
1373 qemu [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
1374 @end example
1376 @item -bt device:@var{dev}[,vlan=@var{n}]
1377 Emulate a bluetooth device @var{dev} and place it in network @var{n}
1378 (default @code{0}). QEMU can only emulate one type of bluetooth devices
1379 currently:
1381 @table @option
1382 @item keyboard
1383 Virtual wireless keyboard implementing the HIDP bluetooth profile.
1384 @end table
1385 @end table
1386 ETEXI
1388 DEFHEADING()
1390 DEFHEADING(Linux/Multiboot boot specific:)
1391 STEXI
1393 When using these options, you can use a given Linux or Multiboot
1394 kernel without installing it in the disk image. It can be useful
1395 for easier testing of various kernels.
1397 @table @option
1398 ETEXI
1400 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
1401 "-kernel bzImage use 'bzImage' as kernel image\n")
1402 STEXI
1403 @item -kernel @var{bzImage}
1404 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
1405 or in multiboot format.
1406 ETEXI
1408 DEF("append", HAS_ARG, QEMU_OPTION_append, \
1409 "-append cmdline use 'cmdline' as kernel command line\n")
1410 STEXI
1411 @item -append @var{cmdline}
1412 Use @var{cmdline} as kernel command line
1413 ETEXI
1415 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
1416 "-initrd file use 'file' as initial ram disk\n")
1417 STEXI
1418 @item -initrd @var{file}
1419 Use @var{file} as initial ram disk.
1421 @item -initrd "@var{file1} arg=foo,@var{file2}"
1423 This syntax is only available with multiboot.
1425 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
1426 first module.
1427 ETEXI
1429 STEXI
1430 @end table
1431 ETEXI
1433 DEFHEADING()
1435 DEFHEADING(Debug/Expert options:)
1437 STEXI
1438 @table @option
1439 ETEXI
1441 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
1442 "-serial dev redirect the serial port to char device 'dev'\n")
1443 STEXI
1444 @item -serial @var{dev}
1445 Redirect the virtual serial port to host character device
1446 @var{dev}. The default device is @code{vc} in graphical mode and
1447 @code{stdio} in non graphical mode.
1449 This option can be used several times to simulate up to 4 serial
1450 ports.
1452 Use @code{-serial none} to disable all serial ports.
1454 Available character devices are:
1455 @table @option
1456 @item vc[:@var{W}x@var{H}]
1457 Virtual console. Optionally, a width and height can be given in pixel with
1458 @example
1459 vc:800x600
1460 @end example
1461 It is also possible to specify width or height in characters:
1462 @example
1463 vc:80Cx24C
1464 @end example
1465 @item pty
1466 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
1467 @item none
1468 No device is allocated.
1469 @item null
1470 void device
1471 @item /dev/XXX
1472 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
1473 parameters are set according to the emulated ones.
1474 @item /dev/parport@var{N}
1475 [Linux only, parallel port only] Use host parallel port
1476 @var{N}. Currently SPP and EPP parallel port features can be used.
1477 @item file:@var{filename}
1478 Write output to @var{filename}. No character can be read.
1479 @item stdio
1480 [Unix only] standard input/output
1481 @item pipe:@var{filename}
1482 name pipe @var{filename}
1483 @item COM@var{n}
1484 [Windows only] Use host serial port @var{n}
1485 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
1486 This implements UDP Net Console.
1487 When @var{remote_host} or @var{src_ip} are not specified
1488 they default to @code{0.0.0.0}.
1489 When not using a specified @var{src_port} a random port is automatically chosen.
1491 If you just want a simple readonly console you can use @code{netcat} or
1492 @code{nc}, by starting qemu with: @code{-serial udp::4555} and nc as:
1493 @code{nc -u -l -p 4555}. Any time qemu writes something to that port it
1494 will appear in the netconsole session.
1496 If you plan to send characters back via netconsole or you want to stop
1497 and start qemu a lot of times, you should have qemu use the same
1498 source port each time by using something like @code{-serial
1499 udp::4555@@:4556} to qemu. Another approach is to use a patched
1500 version of netcat which can listen to a TCP port and send and receive
1501 characters via udp. If you have a patched version of netcat which
1502 activates telnet remote echo and single char transfer, then you can
1503 use the following options to step up a netcat redirector to allow
1504 telnet on port 5555 to access the qemu port.
1505 @table @code
1506 @item Qemu Options:
1507 -serial udp::4555@@:4556
1508 @item netcat options:
1509 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
1510 @item telnet options:
1511 localhost 5555
1512 @end table
1514 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
1515 The TCP Net Console has two modes of operation. It can send the serial
1516 I/O to a location or wait for a connection from a location. By default
1517 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
1518 the @var{server} option QEMU will wait for a client socket application
1519 to connect to the port before continuing, unless the @code{nowait}
1520 option was specified. The @code{nodelay} option disables the Nagle buffering
1521 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
1522 one TCP connection at a time is accepted. You can use @code{telnet} to
1523 connect to the corresponding character device.
1524 @table @code
1525 @item Example to send tcp console to 192.168.0.2 port 4444
1526 -serial tcp:192.168.0.2:4444
1527 @item Example to listen and wait on port 4444 for connection
1528 -serial tcp::4444,server
1529 @item Example to not wait and listen on ip 192.168.0.100 port 4444
1530 -serial tcp:192.168.0.100:4444,server,nowait
1531 @end table
1533 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
1534 The telnet protocol is used instead of raw tcp sockets. The options
1535 work the same as if you had specified @code{-serial tcp}. The
1536 difference is that the port acts like a telnet server or client using
1537 telnet option negotiation. This will also allow you to send the
1538 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
1539 sequence. Typically in unix telnet you do it with Control-] and then
1540 type "send break" followed by pressing the enter key.
1542 @item unix:@var{path}[,server][,nowait]
1543 A unix domain socket is used instead of a tcp socket. The option works the
1544 same as if you had specified @code{-serial tcp} except the unix domain socket
1545 @var{path} is used for connections.
1547 @item mon:@var{dev_string}
1548 This is a special option to allow the monitor to be multiplexed onto
1549 another serial port. The monitor is accessed with key sequence of
1550 @key{Control-a} and then pressing @key{c}. See monitor access
1551 @ref{pcsys_keys} in the -nographic section for more keys.
1552 @var{dev_string} should be any one of the serial devices specified
1553 above. An example to multiplex the monitor onto a telnet server
1554 listening on port 4444 would be:
1555 @table @code
1556 @item -serial mon:telnet::4444,server,nowait
1557 @end table
1559 @item braille
1560 Braille device. This will use BrlAPI to display the braille output on a real
1561 or fake device.
1563 @item msmouse
1564 Three button serial mouse. Configure the guest to use Microsoft protocol.
1565 @end table
1566 ETEXI
1568 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
1569 "-parallel dev redirect the parallel port to char device 'dev'\n")
1570 STEXI
1571 @item -parallel @var{dev}
1572 Redirect the virtual parallel port to host device @var{dev} (same
1573 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
1574 be used to use hardware devices connected on the corresponding host
1575 parallel port.
1577 This option can be used several times to simulate up to 3 parallel
1578 ports.
1580 Use @code{-parallel none} to disable all parallel ports.
1581 ETEXI
1583 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
1584 "-monitor dev redirect the monitor to char device 'dev'\n")
1585 STEXI
1586 @item -monitor @var{dev}
1587 Redirect the monitor to host device @var{dev} (same devices as the
1588 serial port).
1589 The default device is @code{vc} in graphical mode and @code{stdio} in
1590 non graphical mode.
1591 ETEXI
1592 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
1593 "-qmp dev like -monitor but opens in 'control' mode\n")
1595 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
1596 "-mon chardev=[name][,mode=readline|control][,default]\n")
1597 STEXI
1598 @item -mon chardev=[name][,mode=readline|control][,default]
1599 Setup monitor on chardev @var{name}.
1600 ETEXI
1602 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
1603 "-debugcon dev redirect the debug console to char device 'dev'\n")
1604 STEXI
1605 @item -debugcon @var{dev}
1606 Redirect the debug console to host device @var{dev} (same devices as the
1607 serial port). The debug console is an I/O port which is typically port
1608 0xe9; writing to that I/O port sends output to this device.
1609 The default device is @code{vc} in graphical mode and @code{stdio} in
1610 non graphical mode.
1611 ETEXI
1613 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
1614 "-pidfile file write PID to 'file'\n")
1615 STEXI
1616 @item -pidfile @var{file}
1617 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
1618 from a script.
1619 ETEXI
1621 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
1622 "-singlestep always run in singlestep mode\n")
1623 STEXI
1624 @item -singlestep
1625 Run the emulation in single step mode.
1626 ETEXI
1628 DEF("S", 0, QEMU_OPTION_S, \
1629 "-S freeze CPU at startup (use 'c' to start execution)\n")
1630 STEXI
1631 @item -S
1632 Do not start CPU at startup (you must type 'c' in the monitor).
1633 ETEXI
1635 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
1636 "-gdb dev wait for gdb connection on 'dev'\n")
1637 STEXI
1638 @item -gdb @var{dev}
1639 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
1640 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
1641 stdio are reasonable use case. The latter is allowing to start qemu from
1642 within gdb and establish the connection via a pipe:
1643 @example
1644 (gdb) target remote | exec qemu -gdb stdio ...
1645 @end example
1646 ETEXI
1648 DEF("s", 0, QEMU_OPTION_s, \
1649 "-s shorthand for -gdb tcp::%s\n")
1650 STEXI
1651 @item -s
1652 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
1653 (@pxref{gdb_usage}).
1654 ETEXI
1656 DEF("d", HAS_ARG, QEMU_OPTION_d, \
1657 "-d item1,... output log to %s (use -d ? for a list of log items)\n")
1658 STEXI
1659 @item -d
1660 Output log in /tmp/qemu.log
1661 ETEXI
1663 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
1664 "-hdachs c,h,s[,t]\n" \
1665 " force hard disk 0 physical geometry and the optional BIOS\n" \
1666 " translation (t=none or lba) (usually qemu can guess them)\n")
1667 STEXI
1668 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
1669 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
1670 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
1671 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
1672 all those parameters. This option is useful for old MS-DOS disk
1673 images.
1674 ETEXI
1676 DEF("L", HAS_ARG, QEMU_OPTION_L, \
1677 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n")
1678 STEXI
1679 @item -L @var{path}
1680 Set the directory for the BIOS, VGA BIOS and keymaps.
1681 ETEXI
1683 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
1684 "-bios file set the filename for the BIOS\n")
1685 STEXI
1686 @item -bios @var{file}
1687 Set the filename for the BIOS.
1688 ETEXI
1690 #ifdef CONFIG_KVM
1691 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
1692 "-enable-kvm enable KVM full virtualization support\n")
1693 #endif
1694 STEXI
1695 @item -enable-kvm
1696 Enable KVM full virtualization support. This option is only available
1697 if KVM support is enabled when compiling.
1698 ETEXI
1700 #ifdef CONFIG_XEN
1701 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
1702 "-xen-domid id specify xen guest domain id\n")
1703 DEF("xen-create", 0, QEMU_OPTION_xen_create,
1704 "-xen-create create domain using xen hypercalls, bypassing xend\n"
1705 " warning: should not be used when xend is in use\n")
1706 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
1707 "-xen-attach attach to existing xen domain\n"
1708 " xend will use this when starting qemu\n")
1709 #endif
1711 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
1712 "-no-reboot exit instead of rebooting\n")
1713 STEXI
1714 @item -no-reboot
1715 Exit instead of rebooting.
1716 ETEXI
1718 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
1719 "-no-shutdown stop before shutdown\n")
1720 STEXI
1721 @item -no-shutdown
1722 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
1723 This allows for instance switching to monitor to commit changes to the
1724 disk image.
1725 ETEXI
1727 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
1728 "-loadvm [tag|id]\n" \
1729 " start right away with a saved state (loadvm in monitor)\n")
1730 STEXI
1731 @item -loadvm @var{file}
1732 Start right away with a saved state (@code{loadvm} in monitor)
1733 ETEXI
1735 #ifndef _WIN32
1736 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
1737 "-daemonize daemonize QEMU after initializing\n")
1738 #endif
1739 STEXI
1740 @item -daemonize
1741 Daemonize the QEMU process after initialization. QEMU will not detach from
1742 standard IO until it is ready to receive connections on any of its devices.
1743 This option is a useful way for external programs to launch QEMU without having
1744 to cope with initialization race conditions.
1745 ETEXI
1747 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
1748 "-option-rom rom load a file, rom, into the option ROM space\n")
1749 STEXI
1750 @item -option-rom @var{file}
1751 Load the contents of @var{file} as an option ROM.
1752 This option is useful to load things like EtherBoot.
1753 ETEXI
1755 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
1756 "-clock force the use of the given methods for timer alarm.\n" \
1757 " To see what timers are available use -clock ?\n")
1758 STEXI
1759 @item -clock @var{method}
1760 Force the use of the given methods for timer alarm. To see what timers
1761 are available use -clock ?.
1762 ETEXI
1764 HXCOMM Options deprecated by -rtc
1765 DEF("localtime", 0, QEMU_OPTION_localtime, "")
1766 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "")
1768 #ifdef TARGET_I386
1769 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
1770 "-rtc [base=utc|localtime|date][,clock=host|vm][,driftfix=none|slew]\n" \
1771 " set the RTC base and clock, enable drift fix for clock ticks\n")
1772 #else
1773 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
1774 "-rtc [base=utc|localtime|date][,clock=host|vm]\n" \
1775 " set the RTC base and clock\n")
1776 #endif
1778 STEXI
1780 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
1781 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
1782 UTC or local time, respectively. @code{localtime} is required for correct date in
1783 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
1784 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
1786 By default the RTC is driven by the host system time. This allows to use the
1787 RTC as accurate reference clock inside the guest, specifically if the host
1788 time is smoothly following an accurate external reference clock, e.g. via NTP.
1789 If you want to isolate the guest time from the host, even prevent it from
1790 progressing during suspension, you can set @option{clock} to @code{vm} instead.
1792 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
1793 specifically with Windows' ACPI HAL. This option will try to figure out how
1794 many timer interrupts were not processed by the Windows guest and will
1795 re-inject them.
1796 ETEXI
1798 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
1799 "-icount [N|auto]\n" \
1800 " enable virtual instruction counter with 2^N clock ticks per\n" \
1801 " instruction\n")
1802 STEXI
1803 @item -icount [@var{N}|auto]
1804 Enable virtual instruction counter. The virtual cpu will execute one
1805 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
1806 then the virtual cpu speed will be automatically adjusted to keep virtual
1807 time within a few seconds of real time.
1809 Note that while this option can give deterministic behavior, it does not
1810 provide cycle accurate emulation. Modern CPUs contain superscalar out of
1811 order cores with complex cache hierarchies. The number of instructions
1812 executed often has little or no correlation with actual performance.
1813 ETEXI
1815 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
1816 "-watchdog i6300esb|ib700\n" \
1817 " enable virtual hardware watchdog [default=none]\n")
1818 STEXI
1819 @item -watchdog @var{model}
1820 Create a virtual hardware watchdog device. Once enabled (by a guest
1821 action), the watchdog must be periodically polled by an agent inside
1822 the guest or else the guest will be restarted.
1824 The @var{model} is the model of hardware watchdog to emulate. Choices
1825 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
1826 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
1827 controller hub) which is a much more featureful PCI-based dual-timer
1828 watchdog. Choose a model for which your guest has drivers.
1830 Use @code{-watchdog ?} to list available hardware models. Only one
1831 watchdog can be enabled for a guest.
1832 ETEXI
1834 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
1835 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
1836 " action when watchdog fires [default=reset]\n")
1837 STEXI
1838 @item -watchdog-action @var{action}
1840 The @var{action} controls what QEMU will do when the watchdog timer
1841 expires.
1842 The default is
1843 @code{reset} (forcefully reset the guest).
1844 Other possible actions are:
1845 @code{shutdown} (attempt to gracefully shutdown the guest),
1846 @code{poweroff} (forcefully poweroff the guest),
1847 @code{pause} (pause the guest),
1848 @code{debug} (print a debug message and continue), or
1849 @code{none} (do nothing).
1851 Note that the @code{shutdown} action requires that the guest responds
1852 to ACPI signals, which it may not be able to do in the sort of
1853 situations where the watchdog would have expired, and thus
1854 @code{-watchdog-action shutdown} is not recommended for production use.
1856 Examples:
1858 @table @code
1859 @item -watchdog i6300esb -watchdog-action pause
1860 @item -watchdog ib700
1861 @end table
1862 ETEXI
1864 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
1865 "-echr chr set terminal escape character instead of ctrl-a\n")
1866 STEXI
1868 @item -echr @var{numeric_ascii_value}
1869 Change the escape character used for switching to the monitor when using
1870 monitor and serial sharing. The default is @code{0x01} when using the
1871 @code{-nographic} option. @code{0x01} is equal to pressing
1872 @code{Control-a}. You can select a different character from the ascii
1873 control keys where 1 through 26 map to Control-a through Control-z. For
1874 instance you could use the either of the following to change the escape
1875 character to Control-t.
1876 @table @code
1877 @item -echr 0x14
1878 @item -echr 20
1879 @end table
1880 ETEXI
1882 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
1883 "-virtioconsole c\n" \
1884 " set virtio console\n")
1885 STEXI
1886 @item -virtioconsole @var{c}
1887 Set virtio console.
1888 ETEXI
1890 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
1891 "-show-cursor show cursor\n")
1892 STEXI
1893 ETEXI
1895 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
1896 "-tb-size n set TB size\n")
1897 STEXI
1898 ETEXI
1900 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
1901 "-incoming p prepare for incoming migration, listen on port p\n")
1902 STEXI
1903 ETEXI
1905 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
1906 "-nodefaults don't create default devices\n")
1907 STEXI
1908 ETEXI
1910 #ifndef _WIN32
1911 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
1912 "-chroot dir chroot to dir just before starting the VM\n")
1913 #endif
1914 STEXI
1915 @item -chroot @var{dir}
1916 Immediately before starting guest execution, chroot to the specified
1917 directory. Especially useful in combination with -runas.
1918 ETEXI
1920 #ifndef _WIN32
1921 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
1922 "-runas user change to user id user just before starting the VM\n")
1923 #endif
1924 STEXI
1925 @item -runas @var{user}
1926 Immediately before starting guest execution, drop root privileges, switching
1927 to the specified user.
1928 ETEXI
1930 STEXI
1931 @end table
1932 ETEXI
1934 #if defined(TARGET_SPARC) || defined(TARGET_PPC)
1935 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
1936 "-prom-env variable=value\n"
1937 " set OpenBIOS nvram variables\n")
1938 #endif
1939 #if defined(TARGET_ARM) || defined(TARGET_M68K)
1940 DEF("semihosting", 0, QEMU_OPTION_semihosting,
1941 "-semihosting semihosting mode\n")
1942 #endif
1943 #if defined(TARGET_ARM)
1944 DEF("old-param", 0, QEMU_OPTION_old_param,
1945 "-old-param old param mode\n")
1946 #endif
1947 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
1948 "-readconfig <file>\n")
1949 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
1950 "-writeconfig <file>\n"
1951 " read/write config file\n")