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/*
* Copyright (c) 2008 Bret S. Lambert <blambert@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "local.h"
void
fwrite_thread(void *v)
{
FILE *file = v;
int i;
for (i = 0; i < 4096; i++) {
if (fwrite(TEXT, sizeof(char), strlen(TEXT), file) == 0) {
if (feof(file))
break;
printf("OMG!!!\n");
fflush(stdout);
break;
}
}
}
int
main(void)
{
char sfn[24];
char buf[sizeof(TEXT)];
FILE *sfp;
int fd;
strlcpy(sfn, "/tmp/barnacles.XXXXXXXX", sizeof(sfn));
if ((fd = mkstemp(sfn)) == -1 ||
(sfp = fdopen(fd, "w+")) == NULL) {
if (fd != -1) {
unlink(sfn);
close(fd);
}
err(1, "could not open temporary file");
}
run_threads(fwrite_thread, sfp);
while (fread(buf, sizeof(char), strlen(TEXT), sfp)) /* verify */
if (strncmp(buf, TEXT, sizeof(TEXT)))
err(1, "Thread writes were not atomic!!!");
unlink(sfn);
close(fd);
exit(0);
}
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