2 system - issue a shell command
13 This function excutes the shell command found in the srtring, cmd.
14 The return value is system dependent. On POSIX P1003.1 compliant
15 systems the return value is defined by the waitpid system call.
16 Typically a shell command that returns with a 0 exit status will
17 cause this function to return a 0 value. On some systems, a shell
18 command that returns with an exit status of e will cause this
19 function to return e*256. Core dumps, termination due to signals
20 and other waitpid values will change the return value.
22 On POSIX P1003.1 compliant systems, if cmd is empty then this function
23 will determine if the shell is executable. If the shell is executable,
24 0 is returned otherwise non-zero is returned.
34 Sun Jul 9 03:21:48 PDT 1995
46 ## Copyright (C) 1999-2006 Landon Curt Noll
48 ## Calc is open software; you can redistribute it and/or modify it under
49 ## the terms of the version 2.1 of the GNU Lesser General Public License
50 ## as published by the Free Software Foundation.
52 ## Calc is distributed in the hope that it will be useful, but WITHOUT
53 ## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
54 ## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
55 ## Public License for more details.
57 ## A copy of version 2.1 of the GNU Lesser General Public License is
58 ## distributed with calc under the filename COPYING-LGPL. You should have
59 ## received a copy with calc; if not, write to Free Software Foundation, Inc.
60 ## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
62 ## @(#) $Revision: 30.1 $
63 ## @(#) $Id: system,v 30.1 2007/03/16 11:10:42 chongo Exp $
64 ## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/system,v $
66 ## Under source code control: 1995/07/09 03:48:57
67 ## File existed as early as: 1995
69 ## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
70 ## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/