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/* ==== test_execve.c ============================================================
* Copyright (c) 1994 by Chris Provenzano, proven@athena.mit.edu
*
* Description : Test execve() and dup2() calls.
*
* 1.00 94/04/29 proven
* -Started coding this file.
*/
#include <pthread.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <err.h>
#include "test.h"
extern char **environ;
char *argv[] = {
"/bin/echo",
"This message should be displayed after the execve system call",
NULL
};
char * should_succeed = "This line should be displayed\n";
char * should_fail = "Error: This line should NOT be displayed\n";
int
main()
{
int fd;
printf("This is the first message\n");
if (isatty(1)) {
char *ttynm;
ttynm = ttyname(1);
printf("tty is %s\n", ttynm);
if ((fd = open(ttynm, O_RDWR)) < OK)
err(1, "%s", ttynm);
} else
errx(1, "stdout not a tty");
printf("This output is necessary to set the stdout fd to NONBLOCKING\n");
/* do a dup2 */
dup2(fd, 1);
write(1, should_succeed, (size_t)strlen(should_succeed));
#if i_understood_this
_thread_sys_write(1, should_fail, strlen(should_fail));
#endif
if (execve(argv[0], argv, environ) < OK)
err(1, "execve");
PANIC();
}
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