# unlocked-io.m4
# serial 17
dnl Copyright (C) 1998-2006, 2009-2025 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.
dnl This file is offered as-is, without any warranty.

dnl From Jim Meyering.
dnl
dnl See if the glibc *_unlocked I/O macros or functions are available.
dnl Use only those *_unlocked macros or functions that are declared
dnl (because some of them were declared in Solaris 2.5.1 but were removed
dnl in Solaris 2.6, whereas we want binaries built on Solaris 2.5.1 to run
dnl on Solaris 2.6).

AC_DEFUN([gl_FUNC_GLIBC_UNLOCKED_IO],
[
  dnl Persuade glibc and Solaris <stdio.h> to declare
  dnl fgets_unlocked(), fputs_unlocked() etc.
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

  AC_CHECK_DECLS_ONCE([clearerr_unlocked])
  AC_CHECK_DECLS_ONCE([feof_unlocked])
  AC_CHECK_DECLS_ONCE([ferror_unlocked])
  AC_CHECK_DECLS_ONCE([fflush_unlocked])
  AC_CHECK_DECLS_ONCE([fgets_unlocked])
  AC_CHECK_DECLS_ONCE([fileno_unlocked])
  AC_CHECK_DECLS_ONCE([fputc_unlocked])
  AC_CHECK_DECLS_ONCE([fputs_unlocked])
  AC_CHECK_DECLS_ONCE([fread_unlocked])
  AC_CHECK_DECLS_ONCE([fwrite_unlocked])
  AC_CHECK_DECLS_ONCE([getc_unlocked])
  AC_CHECK_DECLS_ONCE([getchar_unlocked])
  AC_CHECK_DECLS_ONCE([putc_unlocked])
  AC_CHECK_DECLS_ONCE([putchar_unlocked])
])
