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Diffstat (limited to '')
| -rw-r--r-- | gl/m4/dup.m4 | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/gl/m4/dup.m4 b/gl/m4/dup.m4 new file mode 100644 index 0000000..005f1ea --- /dev/null +++ b/gl/m4/dup.m4 @@ -0,0 +1,53 @@ +# dup.m4 serial 6 +dnl Copyright (C) 2011-2019 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_FUNC_DUP], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + m4_ifdef([gl_MSVC_INVAL], [ + AC_REQUIRE([gl_MSVC_INVAL]) + if test $HAVE_MSVC_INVALID_PARAMETER_HANDLER = 1; then + REPLACE_DUP=1 + fi + ]) + dnl Replace dup() for supporting the gnulib-defined fchdir() function, + dnl to keep fchdir's bookkeeping up-to-date. + m4_ifdef([gl_FUNC_FCHDIR], [ + gl_TEST_FCHDIR + if test $HAVE_FCHDIR = 0; then + REPLACE_DUP=1 + fi + ]) + AC_CACHE_CHECK([whether dup works], [gl_cv_func_dup_works], + [AC_RUN_IFELSE( + [AC_LANG_PROGRAM([[#include <unistd.h> + #include <fcntl.h> + #include <errno.h>]], + [[/* On OS/2 kLIBC, dup does not work on a directory fd. */ + int fd = open (".", O_RDONLY); + return fd < 0 ? 1 : dup (fd) < 0 ? 2 : 0; + ]]) + ], + [gl_cv_func_dup_works=yes], + [gl_cv_func_dup_works=no], + [case "$host_os" in + # Guess no on native Windows. + mingw*) gl_cv_func_dup_works="guessing no" ;; + *) gl_cv_func_dup_works="guessing yes" ;; + esac + ]) + ]) + case "$gl_cv_func_dup_works" in + *yes) ;; + *) + REPLACE_DUP=1 + ;; + esac +]) + +# Prerequisites of lib/dup.c. +AC_DEFUN([gl_PREREQ_DUP], [:]) |