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| -rw-r--r-- | Lib/distutils/spawn.py | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/Lib/distutils/spawn.py b/Lib/distutils/spawn.py new file mode 100644 index 0000000..24e76ef --- /dev/null +++ b/Lib/distutils/spawn.py @@ -0,0 +1,106 @@ +"""distutils.spawn + +Provides the 'spawn()' function, a front-end to various platform- +specific functions for launching another program in a sub-process.""" + +# created 1999/07/24, Greg Ward + +__rcsid__ = "$Id$" + +import sys, os, string +from distutils.errors import * + + +def spawn (cmd, + search_path=1, + verbose=0, + dry_run=0): + + """Run another program, specified as a command list 'cmd', in a new + process. 'cmd' is just the argument list for the new process, ie. + cmd[0] is the program to run and cmd[1:] are the rest of its + arguments. There is no way to run a program with a name different + from that of its executable. + + If 'search_path' is true (the default), the system's executable + search path will be used to find the program; otherwise, cmd[0] must + be the exact path to the executable. If 'verbose' is true, a + one-line summary of the command will be printed before it is run. + If 'dry_run' is true, the command will not actually be run. + + Raise DistutilsExecError if running the program fails in any way; + just return on success.""" + + if os.name == 'posix': + _spawn_posix (cmd, search_path, verbose, dry_run) + elif os.name == 'windows': # ??? + # XXX should 'args' be cmd[1:] or cmd? + # XXX how do we detect failure? + # XXX how to do this in pre-1.5.2? + # XXX is P_WAIT the correct mode? + # XXX how to make Windows search the path? + if verbose: + print string.join (cmd, ' ') + if not dry_run: + os.spawnv (os.P_WAIT, cmd[0], cmd[1:]) + else: + raise DistutilsPlatformError, \ + "don't know how to spawn programs on platform '%s'" % os.name + +# spawn () + + +def _spawn_posix (cmd, + search_path=1, + verbose=0, + dry_run=0): + + if verbose: + print string.join (cmd, ' ') + if dry_run: + return + exec_fn = search_path and os.execvp or os.execv + + pid = os.fork () + + if pid == 0: # in the child + try: + #print "cmd[0] =", cmd[0] + #print "cmd =", cmd + exec_fn (cmd[0], cmd) + except OSError, e: + sys.stderr.write ("unable to execute %s: %s\n" % + (cmd[0], e.strerror)) + os._exit (1) + + sys.stderr.write ("unable to execute %s for unknown reasons" % cmd[0]) + os._exit (1) + + + else: # in the parent + # Loop until the child either exits or is terminated by a signal + # (ie. keep waiting if it's merely stopped) + while 1: + (pid, status) = os.waitpid (pid, 0) + if os.WIFSIGNALED (status): + raise DistutilsExecError, \ + "command %s terminated by signal %d" % \ + (cmd[0], os.WTERMSIG (status)) + + elif os.WIFEXITED (status): + exit_status = os.WEXITSTATUS (status) + if exit_status == 0: + return # hey, it succeeded! + else: + raise DistutilsExecError, \ + "command %s failed with exit status %d" % \ + (cmd[0], exit_status) + + elif os.WIFSTOPPED (status): + continue + + else: + raise DistutilsExecError, \ + "unknown error executing %s: termination status %d" % \ + (cmd[0], status) +# _spawn_posix () |