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+/* Test the read() function.
+ Copyright (C) 2011-2016 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 <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include <unistd.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (read, ssize_t, (int, void *, size_t));
+
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include "macros.h"
+
+int
+main (void)
+{
+ const char *filename = "test-read.tmp";
+ int fd;
+
+ /* Create a file with a simple contents. */
+ fd = open (filename, O_CREAT | O_WRONLY, 0600);
+ ASSERT (fd >= 0);
+ ASSERT (write (fd, "Hello World", 11) == 11);
+ ASSERT (close (fd) == 0);
+
+ /* Read from the middle of the file. */
+ fd = open (filename, O_RDONLY);
+ ASSERT (fd >= 0);
+ ASSERT (lseek (fd, 6, SEEK_SET) == 6);
+ {
+ char buf[10];
+ ssize_t ret = read (fd, buf, 10);
+ ASSERT (ret == 5);
+ ASSERT (memcmp (buf, "World", 5) == 0);
+ }
+ ASSERT (close (fd) == 0);
+
+ /* Test behaviour for invalid file descriptors. */
+ {
+ char byte;
+ errno = 0;
+ ASSERT (read (-1, &byte, 1) == -1);
+ ASSERT (errno == EBADF);
+ }
+ {
+ char byte;
+ close (99);
+ errno = 0;
+ ASSERT (read (99, &byte, 1) == -1);
+ ASSERT (errno == EBADF);
+ }
+
+ /* Clean up. */
+ unlink (filename);
+
+ return 0;
+}