| """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 |
| |
| __revision__ = "$Id$" |
| |
| 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 == 'nt': |
| _spawn_nt (cmd, search_path, verbose, dry_run) |
| else: |
| raise DistutilsPlatformError, \ |
| "don't know how to spawn programs on platform '%s'" % os.name |
| |
| # spawn () |
| |
| |
| def _nt_quote_args (args): |
| """Obscure quoting command line arguments on NT. |
| Simply quote every argument which contains blanks.""" |
| |
| # XXX this doesn't seem very robust to me -- but if the Windows guys |
| # say it'll work, I guess I'll have to accept it. (What if an arg |
| # contains quotes? What other magic characters, other than spaces, |
| # have to be escaped? Is there an escaping mechanism other than |
| # quoting?) |
| |
| for i in range (len (args)): |
| if string.find (args[i], ' ') == -1: |
| args[i] = '"%s"' % args[i] |
| |
| |
| def _spawn_nt (cmd, |
| search_path=1, |
| verbose=0, |
| dry_run=0): |
| |
| executable = cmd[0] |
| cmd = _nt_quote_args (cmd) |
| if search_path: |
| paths = string.split( os.environ['PATH'], os.pathsep) |
| base,ext = os.path.splitext(executable) |
| if (ext != '.exe'): |
| executable = executable + '.exe' |
| if not os.path.isfile(executable): |
| paths.reverse() # go over the paths and keep the last one |
| for p in paths: |
| f = os.path.join( p, executable ) |
| if os.path.isfile ( f ): |
| # the file exists, we have a shot at spawn working |
| executable = f |
| if verbose: |
| print string.join ([executable] + cmd[1:], ' ') |
| if not dry_run: |
| # spawn for NT requires a full path to the .exe |
| try: |
| rc = os.spawnv (os.P_WAIT, executable, cmd) |
| except OSError, exc: |
| # this seems to happen when the command isn't found |
| raise DistutilsExecError, \ |
| "command '%s' failed: %s" % (cmd[0], exc[-1]) |
| if rc != 0: |
| # and this reflects the command running but failing |
| raise DistutilsExecError, \ |
| "command '%s' failed with exit status %d" % (cmd[0], rc) |
| |
| |
| |
| 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 () |