home *** CD-ROM | disk | FTP | other *** search
/ The Datafile PD-CD 5 / DATAFILE_PDCD5.iso / utilities / p / python / !Python / Lib / Lib2 / py / popen2 < prev    next >
Encoding:
Text File  |  1995-08-07  |  748 b   |  36 lines
  1. import os
  2. import sys
  3. import string
  4.  
  5. MAXFD = 100    # Max number of file descriptors (os.getdtablesize()???)
  6.  
  7. def popen2(cmd):
  8.     cmd = ['/bin/sh', '-c', cmd]
  9.     p2cread, p2cwrite = os.pipe()
  10.     c2pread, c2pwrite = os.pipe()
  11.     pid = os.fork()
  12.     if pid == 0:
  13.         # Child
  14.         os.close(0)
  15.         os.close(1)
  16.         if os.dup(p2cread) <> 0:
  17.             sys.stderr.write('popen2: bad read dup\n')
  18.         if os.dup(c2pwrite) <> 1:
  19.             sys.stderr.write('popen2: bad write dup\n')
  20.         for i in range(3, MAXFD):
  21.             try:
  22.                 os.close(i)
  23.             except:
  24.                 pass
  25.         try:
  26.             os.execv(cmd[0], cmd)
  27.         finally:
  28.             os._exit(1)
  29.         # Shouldn't come here, I guess
  30.         os._exit(1)
  31.     os.close(p2cread)
  32.     tochild = os.fdopen(p2cwrite, 'w')
  33.     os.close(c2pwrite)
  34.     fromchild = os.fdopen(c2pread, 'r')
  35.     return fromchild, tochild
  36.