2 dnl Copyright (C) 2007, 2009, 2010 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_FPURGE],
9 AC_REQUIRE([gl_STDIO_H_DEFAULTS])
10 AC_CHECK_FUNCS_ONCE([fpurge])
11 AC_CHECK_FUNCS_ONCE([__fpurge])
12 AC_CHECK_DECLS([fpurge], , , [[#include <stdio.h>]])
13 if test "x$ac_cv_func_fpurge" = xyes; then
14 # Detect BSD bug. Only cygwin 1.7 is known to be immune.
15 AC_CACHE_CHECK([whether fpurge works], [gl_cv_func_fpurge_works],
16 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
17 ]], [FILE *f = fopen ("conftest.txt", "w+");
19 if (fputc ('a', f) != 'a') return 2;
21 if (fgetc (f) != 'a') return 3;
22 if (fgetc (f) != EOF) return 4;
23 if (fpurge (f) != 0) return 5;
24 if (putc ('b', f) != 'b') return 6;
25 if (fclose (f) != 0) return 7;
26 if ((f = fopen ("conftest.txt", "r")) == NULL) return 8;
27 if (fgetc (f) != 'a') return 9;
28 if (fgetc (f) != 'b') return 10;
29 if (fgetc (f) != EOF) return 11;
30 if (fclose (f) != 0) return 12;
31 if (remove ("conftest.txt") != 0) return 13;
33 [gl_cv_func_fpurge_works=yes], [gl_cv_func_fpurge_works=no],
34 [gl_cv_func_fpurge_works='guessing no'])])
35 if test "x$gl_cv_func_fpurge_works" != xyes; then
42 if test "x$ac_cv_have_decl_fpurge" = xno; then