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+/* An interface to read() that retries after interrupts.
+ Copyright (C) 2002, 2006, 2009-2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Some system calls may be interrupted and fail with errno = EINTR in the
+ following situations:
+ - The process is stopped and restarted (signal SIGSTOP and SIGCONT, user
+ types Ctrl-Z) on some platforms: Mac OS X.
+ - The process receives a signal for which a signal handler was installed
+ with sigaction() with an sa_flags field that does not contain
+ SA_RESTART.
+ - The process receives a signal for which a signal handler was installed
+ with signal() and for which no call to siginterrupt(sig,0) was done,
+ on some platforms: AIX, HP-UX, IRIX, OSF/1, Solaris.
+
+ This module provides a wrapper around read() that handles EINTR. */
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#define SAFE_READ_ERROR ((size_t) -1)
+
+/* Read up to COUNT bytes at BUF from descriptor FD, retrying if interrupted.
+ Return the actual number of bytes read, zero for EOF, or SAFE_READ_ERROR
+ upon error. */
+extern size_t safe_read (int fd, void *buf, size_t count);
+
+
+#ifdef __cplusplus
+}
+#endif