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| author | Bruno Haible <bruno@clisp.org> | 2009-01-16 00:24:35 +0100 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2009-01-16 00:24:35 +0100 |
| commit | 1074f45959f35f8730a097fdc3d142039071ade7 (patch) | |
| tree | c41f135cc44df985afb41a453c71976e28a4ba85 /m4/fflush.m4 | |
| parent | 73a15056d9347aba42002778308ee398a20584c2 (diff) | |
| download | gnulib-1074f45959f35f8730a097fdc3d142039071ade7.tar.gz | |
Make fflush-after-ungetc POSIX compliant on glibc systems.
Diffstat (limited to 'm4/fflush.m4')
| -rw-r--r-- | m4/fflush.m4 | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/m4/fflush.m4 b/m4/fflush.m4 index 97f12843d4..da30e1fe67 100644 --- a/m4/fflush.m4 +++ b/m4/fflush.m4 @@ -1,6 +1,6 @@ -# fflush.m4 serial 6 +# fflush.m4 serial 7 -# Copyright (C) 2007-2008 Free Software Foundation, Inc. +# Copyright (C) 2007-2009 Free Software Foundation, Inc. # This file is free software; the Free Software Foundation # gives unlimited permission to copy and/or distribute it, # with or without modifications, as long as this notice is preserved. @@ -22,6 +22,7 @@ AC_DEFUN([gl_FUNC_FFLUSH], ]], [[FILE *f = fopen ("conftest.txt", "r"); char buffer[10]; int fd; + int c; if (f == NULL) return 1; fd = fileno (f); @@ -30,17 +31,31 @@ AC_DEFUN([gl_FUNC_FFLUSH], /* For deterministic results, ensure f read a bigger buffer. */ if (lseek (fd, 0, SEEK_CUR) == 5) return 3; - /* POSIX requires fflush-fseek to set file offset of fd. */ + /* POSIX requires fflush-fseek to set file offset of fd. This fails + on BSD systems and on mingw. */ if (fflush (f) != 0 || fseek (f, 0, SEEK_CUR) != 0) return 4; if (lseek (fd, 0, SEEK_CUR) != 5) return 5; - /* TODO: Verify behaviour of fflush after ungetc, see - <http://lists.gnu.org/archive/html/bug-gnulib/2008-03/msg00131.html>. */ + /* Verify behaviour of fflush after ungetc. See + <http://www.opengroup.org/austin/aardvark/latest/xshbug3.txt> */ + /* Verify behaviour of fflush after a backup ungetc. This fails on + mingw. */ + c = fgetc (f); + ungetc (c, f); + fflush (f); + if (fgetc (f) != c) + return 6; + /* Verify behaviour of fflush after a non-backup ungetc. This fails + on glibc 2.8 and on BSD systems. */ + c = fgetc (f); + ungetc ('@', f); + fflush (f); + if (fgetc (f) != c) + return 7; return 0; ]])], [gl_cv_func_fflush_stdin=yes], [gl_cv_func_fflush_stdin=no], - [dnl Pessimistically assume fflush is broken. This is wrong for - dnl at least glibc and cygwin; but lib/fflush.c takes this into account. + [dnl Pessimistically assume fflush is broken. gl_cv_func_fflush_stdin=no]) rm conftest.txt ]) |