1# fstatat.m4 serial 4 2dnl Copyright (C) 2004-2021 Free Software Foundation, Inc. 3dnl This file is free software; the Free Software Foundation 4dnl gives unlimited permission to copy and/or distribute it, 5dnl with or without modifications, as long as this notice is preserved. 6 7# Written by Jim Meyering. 8 9# If we have the fstatat function, and it has the bug (in AIX 7.1) 10# that it does not fill in st_size correctly, use the replacement function. 11AC_DEFUN([gl_FUNC_FSTATAT], 12[ 13 AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS]) 14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) 15 AC_REQUIRE([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK]) 16 AC_REQUIRE([AC_CANONICAL_HOST]) 17 AC_CHECK_FUNCS_ONCE([fstatat]) 18 19 if test $ac_cv_func_fstatat = no; then 20 HAVE_FSTATAT=0 21 else 22 dnl Test for an AIX 7.1 bug; see 23 dnl <https://lists.gnu.org/r/bug-tar/2011-09/msg00015.html>. 24 AC_CACHE_CHECK([whether fstatat (..., 0) works], 25 [gl_cv_func_fstatat_zero_flag], 26 [AC_RUN_IFELSE( 27 [AC_LANG_SOURCE( 28 [[ 29 #include <fcntl.h> 30 #include <sys/stat.h> 31 int 32 main (void) 33 { 34 struct stat a; 35 return fstatat (AT_FDCWD, ".", &a, 0) != 0; 36 } 37 ]])], 38 [gl_cv_func_fstatat_zero_flag=yes], 39 [gl_cv_func_fstatat_zero_flag=no], 40 [case "$host_os" in 41 aix*) gl_cv_func_fstatat_zero_flag="guessing no";; 42 *) gl_cv_func_fstatat_zero_flag="guessing yes";; 43 esac 44 ]) 45 ]) 46 47 case $gl_cv_func_fstatat_zero_flag+$gl_cv_func_lstat_dereferences_slashed_symlink in 48 *yes+*yes) ;; 49 *) REPLACE_FSTATAT=1 ;; 50 esac 51 52 case $host_os in 53 solaris*) 54 REPLACE_FSTATAT=1 ;; 55 esac 56 57 case $REPLACE_FSTATAT,$gl_cv_func_fstatat_zero_flag in 58 1,*yes) 59 AC_DEFINE([HAVE_WORKING_FSTATAT_ZERO_FLAG], [1], 60 [Define to 1 if fstatat (..., 0) works. 61 For example, it does not work in AIX 7.1.]) 62 ;; 63 esac 64 fi 65]) 66