resource/sys/resource.h

   1 /* Copyright (C) 1992, 1994 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #ifndef _SYS_RESOURCE_H
  20
  21 #define _SYS_RESOURCE_H 1
  22 #include <features.h>
  23
  24 __BEGIN_DECLS
  25
  26 /* Get the system-dependent definitions of RLIM_*.  */
  27 #include <resourcebits.h>
  28
  29 struct rlimit
  30   {
  31     /* The current (soft) limit.  */
  32     int rlim_cur;
  33     /* The hard limit.  */
  34     int rlim_max;
  35   };
  36
  37 /* Value used to indicate that there is no limit.  */
  38 #define RLIM_INFINITY 0x7fffffff
  39
  40 /* Put the soft and hard limits for RESOURCE in *RLIMITS.
  41    Returns 0 if successful, -1 if not (and sets errno).  */
  42 int getrlimit __P ((enum __rlimit_resource __resource,
  43                     struct rlimit * __rlimits));
  44
  45 /* Set the soft and hard limits for RESOURCE to *RLIMITS.
  46    Only the super-user can increase hard limits.
  47    Return 0 if successful, -1 if not (and sets errno).  */
  48 int setrlimit __P ((enum __rlimit_resource __resource,
  49                     struct rlimit * __rlimits));
  50
  51
  52 /* Whose usage statistics do you want?  */
  53 enum __rusage_who
  54 /* The macro definitions are necessary because some programs want
  55    to test for operating system features with #ifdef RUSAGE_SELF.
  56    In ANSI C the reflexive definition is a no-op.  */
  57   {
  58     /* The calling process.  */
  59     RUSAGE_SELF = 0,
  60 #define RUSAGE_SELF     RUSAGE_SELF
  61     /* All of its terminated child processes.  */
  62     RUSAGE_CHILDREN = -1,
  63 #define RUSAGE_CHILDREN RUSAGE_CHILDREN
  64   };
  65
  66 #include <sys/time.h>           /* For `struct timeval'.  */
  67
  68 /* Structure which says how much of each resource has been used.  */
  69 struct rusage
  70   {
  71     /* Total amount of user time used.  */
  72     struct timeval ru_utime;
  73     /* Total amount of system time used.  */
  74     struct timeval ru_stime;
  75     /* Maximum resident set size (in kilobytes).  */
  76     long ru_maxrss;
  77     /* Amount of sharing of text segment memory
  78        with other processes (kilobyte-seconds).  */
  79     long ru_ixrss;
  80     /* Amount of data segment memory used (kilobyte-seconds).  */
  81     long ru_idrss;
  82     /* Amount of stack memory used (kilobyte-seconds).  */
  83     long ru_isrss;
  84     /* Number of soft page faults (i.e. those serviced by reclaiming
  85        a page from the list of pages awaiting reallocation.  */
  86     long ru_minflt;
  87     /* Number of hard page faults (i.e. those that required I/O).  */
  88     long ru_majflt;
  89     /* Number of times a process was swapped out of physical memory.  */
  90     long ru_nswap;
  91     /* Number of input operations via the file system.  Note: This
  92        and `ru_oublock' do not include operations with the cache.  */
  93     long ru_inblock;
  94     /* Number of output operations via the file system.  */
  95     long ru_oublock;
  96     /* Number of IPC messages sent.  */
  97     long ru_msgsnd;
  98     /* Number of IPC messages received.  */
  99     long ru_msgrcv;
 100     /* Number of signals delivered.  */
 101     long ru_nsignals;
 102     /* Number of voluntary context switches, i.e. because the process
 103        gave up the process before it had to (usually to wait for some
 104        resource to be available).  */
 105     long ru_nvcsw;
 106     /* Number of involuntary context switches, i.e. a higher priority process
 107        became runnable or the current process used up its time slice.  */
 108     long ru_nivcsw;
 109   };
 110
 111 /* Return resource usage information on process indicated by WHO
 112    and put it in *USAGE.  Returns 0 for success, -1 for failure.  */
 113 int __getrusage __P ((enum __rusage_who __who, struct rusage * __usage));
 114 int getrusage __P ((enum __rusage_who __who, struct rusage * __usage));
 115
 116 /* Function depends on CMD:
 117    1 = Return the limit on the size of a file, in units of 512 bytes.
 118    2 = Set the limit on the size of a file to NEWLIMIT.  Only the
 119        super-user can increase the limit.
 120    3 = Return the maximum possible address of the data segment.
 121    4 = Return the maximum number of files that the calling process can open.
 122    Returns -1 on errors.  */
 123 long int __ulimit __P ((int __cmd, long int __newlimit));
 124 long int ulimit __P ((int __cmd, long int __newlimit));
 125
 126
 127 /* Priority limits.  */
 128 #define PRIO_MIN        -20     /* Minimum priority a process can have.  */
 129 #define PRIO_MAX        20      /* Maximum priority a process can have.  */
 130
 131 /* The type of the WHICH argument to `getpriority' and `setpriority',
 132    indicating what flavor of entity the WHO argument specifies.  */
 133 enum __priority_which
 134   {
 135     PRIO_PROCESS = 0,           /* WHO is a process ID.  */
 136     PRIO_PGRP = 1,              /* WHO is a process group ID.  */
 137     PRIO_USER = 2,              /* WHO is a user ID.  */
 138   };
 139
 140 /* Return the highest priority of any process specified by WHICH and WHO
 141    (see above); if WHO is zero, the current process, process group, or user
 142    (as specified by WHO) is used.  A lower priority number means higher
 143    priority.  Priorities range from PRIO_MIN to PRIO_MAX (above).  */
 144 extern int getpriority __P ((enum __priority_which __which, int __who));
 145
 146 /* Set the priority of all processes specified by WHICH and WHO (see above)
 147    to PRIO.  Returns 0 on success, -1 on errors.  */
 148 extern int setpriority __P ((enum __priority_which __which, int __who,
 149                              int __prio));
 150
 151
 152 __END_DECLS
 153
 154 #endif /* resource.h  */