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diff --git a/lib/stdio-read.c b/lib/stdio-read.c
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+/* POSIX compatible FILE stream read function.
+ Copyright (C) 2008-2023 Free Software Foundation, Inc.
+ Written by Bruno Haible <bruno@clisp.org>, 2011.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <stdio.h>
+
+/* Replace these functions only if module 'nonblocking' is requested. */
+#if GNULIB_NONBLOCKING
+
+/* On native Windows platforms, when read() is called on a non-blocking pipe
+ with an empty buffer, ReadFile() fails with error GetLastError() =
+ ERROR_NO_DATA, and read() in consequence fails with error EINVAL. This
+ read() function is at the basis of the function which fills the buffer of
+ a FILE stream. */
+
+# if defined _WIN32 && ! defined __CYGWIN__
+
+# include <errno.h>
+# include <io.h>
+
+# define WIN32_LEAN_AND_MEAN /* avoid including junk */
+# include <windows.h>
+
+# if GNULIB_MSVC_NOTHROW
+# include "msvc-nothrow.h"
+# else
+# include <io.h>
+# endif
+
+/* Don't assume that UNICODE is not defined. */
+# undef GetNamedPipeHandleState
+# define GetNamedPipeHandleState GetNamedPipeHandleStateA
+
+# define CALL_WITH_ERRNO_FIX(RETTYPE, EXPRESSION, FAILED) \
+ if (ferror (stream)) \
+ return (EXPRESSION); \
+ else \
+ { \
+ RETTYPE ret; \
+ SetLastError (0); \
+ ret = (EXPRESSION); \
+ if (FAILED) \
+ { \
+ if (GetLastError () == ERROR_NO_DATA && ferror (stream)) \
+ { \
+ int fd = fileno (stream); \
+ if (fd >= 0) \
+ { \
+ HANDLE h = (HANDLE) _get_osfhandle (fd); \
+ if (GetFileType (h) == FILE_TYPE_PIPE) \
+ { \
+ /* h is a pipe or socket. */ \
+ DWORD state; \
+ if (GetNamedPipeHandleState (h, &state, NULL, NULL, \
+ NULL, NULL, 0) \
+ && (state & PIPE_NOWAIT) != 0) \
+ /* h is a pipe in non-blocking mode. \
+ Change errno from EINVAL to EAGAIN. */ \
+ errno = EAGAIN; \
+ } \
+ } \
+ } \
+ } \
+ return ret; \
+ }
+
+/* Enable this function definition only if gnulib's <stdio.h> has prepared it.
+ Otherwise we get a function definition conflict with mingw64's <stdio.h>. */
+# if GNULIB_SCANF
+int
+scanf (const char *format, ...)
+{
+ int retval;
+ va_list args;
+
+ va_start (args, format);
+ retval = vfscanf (stdin, format, args);
+ va_end (args);
+
+ return retval;
+}
+# endif
+
+/* Enable this function definition only if gnulib's <stdio.h> has prepared it.
+ Otherwise we get a function definition conflict with mingw64's <stdio.h>. */
+# if GNULIB_FSCANF
+int
+fscanf (FILE *stream, const char *format, ...)
+{
+ int retval;
+ va_list args;
+
+ va_start (args, format);
+ retval = vfscanf (stream, format, args);
+ va_end (args);
+
+ return retval;
+}
+# endif
+
+/* Enable this function definition only if gnulib's <stdio.h> has prepared it.
+ Otherwise we get a function definition conflict with mingw64's <stdio.h>. */
+# if GNULIB_VSCANF
+int
+vscanf (const char *format, va_list args)
+{
+ return vfscanf (stdin, format, args);
+}
+# endif
+
+/* Enable this function definition only if gnulib's <stdio.h> has prepared it.
+ Otherwise we get a function definition conflict with mingw64's <stdio.h>. */
+# if GNULIB_VFSCANF
+int
+vfscanf (FILE *stream, const char *format, va_list args)
+#undef vfscanf
+{
+ CALL_WITH_ERRNO_FIX (int, vfscanf (stream, format, args), ret == EOF)
+}
+# endif
+
+int
+getchar (void)
+{
+ return fgetc (stdin);
+}
+
+int
+fgetc (FILE *stream)
+#undef fgetc
+{
+ CALL_WITH_ERRNO_FIX (int, fgetc (stream), ret == EOF)
+}
+
+char *
+fgets (char *s, int n, FILE *stream)
+#undef fgets
+{
+ CALL_WITH_ERRNO_FIX (char *, fgets (s, n, stream), ret == NULL)
+}
+
+/* We intentionally don't bother to fix gets. */
+
+size_t
+fread (void *ptr, size_t s, size_t n, FILE *stream)
+#undef fread
+{
+ CALL_WITH_ERRNO_FIX (size_t, fread (ptr, s, n, stream), ret < n)
+}
+
+# endif
+#endif