1 files changed, 51 insertions, 0 deletions
diff --git a/m4/fdopen.m4 b/m4/fdopen.m4
new file mode 100644
index 0000000..6b3909b
--- /dev/null
+++ b/m4/fdopen.m4
@@ -0,0 +1,51 @@
+# fdopen.m4 serial 5
+dnl Copyright (C) 2011-2023 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_FDOPEN],
+[
+  AC_REQUIRE([gl_STDIO_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_FDOPEN=1
+    fi
+  ])
+  if test $REPLACE_FDOPEN = 0; then
+    dnl Test whether fdopen() sets errno when it fails due to a bad fd argument.
+    AC_CACHE_CHECK([whether fdopen sets errno], [gl_cv_func_fdopen_works],
+      [
+        AC_RUN_IFELSE(
+          [AC_LANG_SOURCE([[
+#include <stdio.h>
+#include <errno.h>
+]GL_MDA_DEFINES[
+int
+main (void)
+{
+  FILE *fp;
+  errno = 0;
+  fp = fdopen (-1, "r");
+  if (fp == NULL && errno == 0)
+    return 1;
+  return 0;
+}]])],
+          [gl_cv_func_fdopen_works=yes],
+          [gl_cv_func_fdopen_works=no],
+          [case "$host_os" in
+             mingw*) gl_cv_func_fdopen_works="guessing no" ;;
+             *)      gl_cv_func_fdopen_works="guessing yes" ;;
+           esac
+          ])
+      ])
+    case "$gl_cv_func_fdopen_works" in
+      *no) REPLACE_FDOPEN=1 ;;
+    esac
+  fi
+])
+
+dnl Prerequisites of lib/fdopen.c.
+AC_DEFUN([gl_PREREQ_FDOPEN], [])