1 /* arg-max.h -- ARG_MAX and _SC_ARG_MAX checks and manipulations
3 Copyright (C) 2010 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 Written by James Youngman.
21 #define INC_ARG_MAX_H 1
23 #include <unistd.h> /* for sysconf() */
26 /* On Interix, _SC_ARG_MAX yields a value that (according to
27 * http://lists.gnu.org/archive/html/bug-findutils/2010-10/msg00047.html)
28 * actually does not work (i.e. it is larger than the real limit).
29 * The value of ARG_MAX is reportedly smaller than the real limit.
31 * I considered a configure test for this which allocates an argument
32 * list longer than ARG_MAX but shorter than _SC_ARG_MAX and then
33 * tries to exec something, but this will not work for us when
34 * cross-compiling if the target is Interix.
36 * Although buildcmd has heuristics for dealing with the possibility
37 * that execve fails due to length limits in the implementation, it
38 * assumed that changes are only necessary if execve fails with errno
39 * set to E2BIG. On Interix, this failure mode of execve appears to
40 * set errno to ENOMEM.
42 * Since we may undefine _SC_ARG_MAX, we must include this header after
46 # define BC_SC_ARG_MAX_IS_UNRELIABLE 1