1 /* Copyright (C) 1995,1996,1997,1998,2000,2001, 2003, 2004 Free Software
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include <signal.h> /* for SIG constants */
27 #include <stdlib.h> /* for getenv */
29 #include "libguile/_scm.h"
31 #include "libguile/scmsigs.h"
32 #include "libguile/strings.h"
34 #include "libguile/validate.h"
35 #include "libguile/simpos.h"
36 #include "libguile/dynwind.h"
45 # include <sys/wait.h>
55 SCM_DEFINE (scm_system, "system", 0, 1, 0,
57 "Execute @var{cmd} using the operating system's \"command\n"
58 "processor\". Under Unix this is usually the default shell\n"
59 "@code{sh}. The value returned is @var{cmd}'s exit status as\n"
60 "returned by @code{waitpid}, which can be interpreted using\n"
61 "@code{status:exit-val} and friends.\n"
63 "If @code{system} is called without arguments, return a boolean\n"
64 "indicating whether the command processor is available.")
65 #define FUNC_NAME s_scm_system
73 return scm_from_bool(rv);
75 SCM_VALIDATE_STRING (1, cmd);
77 c_cmd = scm_to_locale_string (cmd);
79 eno = errno; free (c_cmd); errno = eno;
80 if (rv == -1 || (rv == 127 && errno != 0))
82 return scm_from_int (rv);
85 #endif /* HAVE_SYSTEM */
92 free_string_pointers (void *data)
94 scm_i_free_string_pointers ((char **)data);
97 SCM_DEFINE (scm_system_star, "system*", 0, 0, 1,
99 "Execute the command indicated by @var{args}. The first element must\n"
100 "be a string indicating the command to be executed, and the remaining\n"
101 "items must be strings representing each of the arguments to that\n"
104 "This function returns the exit status of the command as provided by\n"
105 "@code{waitpid}. This value can be handled with @code{status:exit-val}\n"
106 "and the related functions.\n"
108 "@code{system*} is similar to @code{system}, but accepts only one\n"
109 "string per-argument, and performs no shell interpretation. The\n"
110 "command is executed using fork and execlp. Accordingly this function\n"
111 "may be safer than @code{system} in situations where shell\n"
112 "interpretation is not required.\n"
114 "Example: (system* \"echo\" \"foo\" \"bar\")")
115 #define FUNC_NAME s_scm_system_star
117 if (scm_is_null (args))
118 SCM_WRONG_NUM_ARGS ();
120 if (scm_is_pair (args))
130 scm_dynwind_begin (0);
132 /* allocate before fork */
133 execargv = scm_i_allocate_string_pointers (args);
134 scm_dynwind_unwind_handler (free_string_pointers, execargv,
135 SCM_F_WIND_EXPLICITLY);
137 /* make sure the child can't kill us (as per normal system call) */
138 sig_ign = scm_from_long ((unsigned long) SIG_IGN);
139 sigint = scm_from_int (SIGINT);
140 sigquit = scm_from_int (SIGQUIT);
141 oldint = scm_sigaction (sigint, sig_ign, SCM_UNDEFINED);
142 oldquit = scm_sigaction (sigquit, sig_ign, SCM_UNDEFINED);
148 execvp (execargv[0], execargv);
157 int wait_result, status;
162 SCM_SYSCALL (wait_result = waitpid (pid, &status, 0));
163 if (wait_result == -1)
165 scm_sigaction (sigint, SCM_CAR (oldint), SCM_CDR (oldint));
166 scm_sigaction (sigquit, SCM_CAR (oldquit), SCM_CDR (oldquit));
169 return scm_from_int (status);
173 SCM_WRONG_TYPE_ARG (1, args);
176 #endif /* HAVE_WAITPID */
177 #endif /* HAVE_SYSTEM */
180 SCM_DEFINE (scm_getenv, "getenv", 1, 0, 0,
182 "Looks up the string @var{name} in the current environment. The return\n"
183 "value is @code{#f} unless a string of the form @code{NAME=VALUE} is\n"
184 "found, in which case the string @code{VALUE} is returned.")
185 #define FUNC_NAME s_scm_getenv
188 char *var = scm_to_locale_string (nam);
191 return val ? scm_from_locale_string (val) : SCM_BOOL_F;
195 /* simple exit, without unwinding the scheme stack or flushing ports. */
196 SCM_DEFINE (scm_primitive_exit, "primitive-exit", 0, 1, 0,
198 "Terminate the current process without unwinding the Scheme\n"
199 "stack. The exit status is @var{status} if supplied, otherwise\n"
201 #define FUNC_NAME s_scm_primitive_exit
204 if (!SCM_UNBNDP (status))
205 cstatus = scm_to_int (status);
210 SCM_DEFINE (scm_primitive__exit, "primitive-_exit", 0, 1, 0,
212 "Terminate the current process using the _exit() system call and\n"
213 "without unwinding the Scheme stack. The exit status is\n"
214 "@var{status} if supplied, otherwise zero.\n"
216 "This function is typically useful after a fork, to ensure no\n"
217 "Scheme cleanups or @code{atexit} handlers are run (those\n"
218 "usually belonging in the parent rather than the child).")
219 #define FUNC_NAME s_scm_primitive__exit
222 if (!SCM_UNBNDP (status))
223 cstatus = scm_to_int (status);
233 #include "libguile/simpos.x"