monitor/extra/Gnuplot/gp_win32.py

   1 # $Id: gp_win32.py 292 2006-03-03 09:49:04Z mhagger $
   2
   3 # Copyright (C) 1999-2003 Michael Haggerty <mhagger@alum.mit.edu>
   4 #
   5 # This file is licensed under the GNU Lesser General Public License
   6 # (LGPL).  See LICENSE.txt for details.
   7
   8 """gp_win32 -- an interface to gnuplot for Windows.
   9
  10 """
  11
  12 import Errors
  13
  14 # ############ Configuration variables: ################################
  15
  16 class GnuplotOpts:
  17     """The configuration options for gnuplot under windows.
  18
  19     See gp_unix.py for details about the meaning of these options.
  20     Please let me know if you know better choices for these settings.
  21
  22     """
  23
  24     # Command to start up the gnuplot program.  Note that on windows
  25     # the main gnuplot program cannot be used directly because it can
  26     # not read commands from standard input.  See README for more
  27     # information.
  28     #
  29     # If pgnuplot is in a subdirectory with spaces in its name, extra
  30     # quoting is required for windows for it to launch gnuplot.
  31     # Moreover, it is suggested to use a raw string to avoid having to
  32     # quote backslashes in the filename.  Example:
  33     #
  34     #     gnuplot_command = r'"C:\Program Files\gp371w32\pgnuplot.exe"'
  35     gnuplot_command = r'pgnuplot.exe'
  36
  37     # The '-persist' option is not supported on windows:
  38     recognizes_persist = 0
  39
  40     # As far as I know, gnuplot under windows can use binary data:
  41     recognizes_binary_splot = 1
  42
  43     # Apparently gnuplot on windows can use inline data, but we use
  44     # non-inline data (i.e., temporary files) by default for no
  45     # special reason:
  46     prefer_inline_data = 0
  47
  48     # os.mkfifo is apparently not supported under Windows.
  49     support_fifo = 0
  50     prefer_fifo_data = 0
  51
  52     # The default choice for the 'set term' command (to display on
  53     # screen):
  54     default_term = 'windows'
  55
  56     # According to the gnuplot help manual, the following can be used
  57     # to print directly to a printer under windows.  (Of course it
  58     # won't help if your printer can't handle postscript!)
  59     default_lpr = 'PRN'
  60
  61     # Used the 'enhanced' option of postscript by default?  Set to
  62     # None (*not* 0!) if your version of gnuplot doesn't support
  63     # enhanced postscript.
  64     prefer_enhanced_postscript = 1
  65
  66 # ############ End of configuration options ############################
  67
  68
  69 try:
  70     from sys import hexversion
  71 except ImportError:
  72     hexversion = 0
  73
  74 if hexversion >= 0x02000000:
  75     # Apparently at least as of Python 2.0b1, popen support for
  76     # windows is adequate.  Give that a try:
  77     from os import popen
  78 else:
  79     # For earlier versions, you have to have the win32 extensions
  80     # installed and we use the popen that it provides.
  81     from win32pipe import popen
  82
  83
  84 # Mac doesn't recognize persist.
  85 def test_persist():
  86     return 0
  87
  88
  89 class GnuplotProcess:
  90     """Unsophisticated interface to a running gnuplot program.
  91
  92     See gp_unix.py for usage information.
  93
  94     """
  95
  96     def __init__(self, persist=0):
  97         """Start a gnuplot process.
  98
  99         Create a 'GnuplotProcess' object.  This starts a gnuplot
 100         program and prepares to write commands to it.
 101
 102         Keyword arguments:
 103
 104             'persist' -- the '-persist' option is not supported under
 105                 Windows so this argument must be zero.
 106
 107         """
 108
 109         if persist:
 110             raise Errors.OptionError(
 111                 '-persist is not supported under Windows!')
 112
 113         self.gnuplot = popen(GnuplotOpts.gnuplot_command, 'w')
 114
 115         # forward write and flush methods:
 116         self.write = self.gnuplot.write
 117         self.flush = self.gnuplot.flush
 118
 119     def close(self):
 120         if self.gnuplot is not None:
 121             self.gnuplot.close()
 122             self.gnuplot = None
 123
 124     def __del__(self):
 125         self.close()
 126
 127     def __call__(self, s):
 128         """Send a command string to gnuplot, followed by newline."""
 129
 130         self.write(s + '\n')
 131         self.flush()
 132
 133