mirror of
				https://github.com/python/cpython.git
				synced 2025-10-31 02:15:10 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			99 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			99 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| import os
 | |
| import sys
 | |
| import string
 | |
| 
 | |
| MAXFD = 256     # Max number of file descriptors (os.getdtablesize()???)
 | |
| 
 | |
| _active = []
 | |
| 
 | |
| def _cleanup():
 | |
|     for inst in _active[:]:
 | |
|         inst.poll()
 | |
| 
 | |
| class Popen3:
 | |
|     def __init__(self, cmd, capturestderr=0, bufsize=-1):
 | |
|         if type(cmd) == type(''):
 | |
|             cmd = ['/bin/sh', '-c', cmd]
 | |
|         p2cread, p2cwrite = os.pipe()
 | |
|         c2pread, c2pwrite = os.pipe()
 | |
|         if capturestderr:
 | |
|             errout, errin = os.pipe()
 | |
|         self.pid = os.fork()
 | |
|         if self.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.execvp(cmd[0], cmd)
 | |
|             finally:
 | |
|                 os._exit(1)
 | |
|             # Shouldn't come here, I guess
 | |
|             os._exit(1)
 | |
|         os.close(p2cread)
 | |
|         self.tochild = os.fdopen(p2cwrite, 'w', bufsize)
 | |
|         os.close(c2pwrite)
 | |
|         self.fromchild = os.fdopen(c2pread, 'r', bufsize)
 | |
|         if capturestderr:
 | |
|             os.close(errin)
 | |
|             self.childerr = os.fdopen(errout, 'r', bufsize)
 | |
|         else:
 | |
|             self.childerr = None
 | |
|         self.sts = -1 # Child not completed yet
 | |
|         _active.append(self)
 | |
|     def poll(self):
 | |
|         if self.sts < 0:
 | |
|             try:
 | |
|                 pid, sts = os.waitpid(self.pid, os.WNOHANG)
 | |
|                 if pid == self.pid:
 | |
|                     self.sts = sts
 | |
|                     _active.remove(self)
 | |
|             except os.error:
 | |
|                 pass
 | |
|         return self.sts
 | |
|     def wait(self):
 | |
|         pid, sts = os.waitpid(self.pid, 0)
 | |
|         if pid == self.pid:
 | |
|             self.sts = sts
 | |
|             _active.remove(self)
 | |
|         return self.sts
 | |
| 
 | |
| def popen2(cmd, bufsize=-1):
 | |
|     _cleanup()
 | |
|     inst = Popen3(cmd, 0, bufsize)
 | |
|     return inst.fromchild, inst.tochild
 | |
| 
 | |
| def popen3(cmd, bufsize=-1):
 | |
|     _cleanup()
 | |
|     inst = Popen3(cmd, 1, bufsize)
 | |
|     return inst.fromchild, inst.tochild, inst.childerr
 | |
| 
 | |
| def _test():
 | |
|     teststr = "abc\n"
 | |
|     print "testing popen2..."
 | |
|     r, w = popen2('cat')
 | |
|     w.write(teststr)
 | |
|     w.close()
 | |
|     assert r.read() == teststr
 | |
|     print "testing popen3..."
 | |
|     r, w, e = popen3(['cat'])
 | |
|     w.write(teststr)
 | |
|     w.close()
 | |
|     assert r.read() == teststr
 | |
|     assert e.read() == ""
 | |
|     _cleanup()
 | |
|     assert not _active
 | |
|     print "All OK"
 | |
| 
 | |
| if __name__ == '__main__':
 | |
|     _test()
 | 
