| import os |
| import sys |
| import string |
| |
| MAXFD = 100 # Max number of file descriptors (os.getdtablesize()???) |
| |
| def _popen2(cmd, capturestderr=0): |
| cmd = ['/bin/sh', '-c', cmd] |
| p2cread, p2cwrite = os.pipe() |
| c2pread, c2pwrite = os.pipe() |
| if capturestderr: |
| errout, errin = os.pipe() |
| pid = os.fork() |
| if pid == 0: |
| # Child |
| os.close(0) |
| os.close(1) |
| if os.dup(p2cread) <> 0: |
| sys.stderr.write('popen2: bad read dup\n') |
| if os.dup(c2pwrite) <> 1: |
| sys.stderr.write('popen2: bad write dup\n') |
| if capturestderr: |
| os.close(2) |
| if os.dup(errin) <> 2: pass |
| for i in range(3, MAXFD): |
| try: |
| os.close(i) |
| except: pass |
| try: |
| os.execv(cmd[0], cmd) |
| finally: |
| os._exit(1) |
| # Shouldn't come here, I guess |
| os._exit(1) |
| os.close(p2cread) |
| tochild = os.fdopen(p2cwrite, 'w') |
| os.close(c2pwrite) |
| fromchild = os.fdopen(c2pread, 'r') |
| if capturestderr: |
| os.close(errin) |
| childerr = os.fdopen(errout, 'r') |
| return fromchild, tochild, childerr |
| else: |
| return fromchild, tochild, None |
| |
| def popen2(cmd): |
| return _popen2(cmd, 0)[:2] |
| |
| def popen3(cmd): |
| return _popen2(cmd, 1) |