HP-UX Reference (11i v1 05/09) - 2 System Calls (vol 5)

p
ptrace(2) ptrace(2)
printf("Child: exec failed\n");
exit(0);
}
parent()
{
close(filed[0]);
/* Before child does an exec, attach it and set its event flag. */
if (ptrace(PT_ATTACH,pid)) /* failed to attach process */
printf("Parent: Failed to attach child\n");
if (pid != wait(&status)) /* wait failed */
printf("Parent: attach failed with wrong wait status\n");
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
printf("Parent: SIGTRAP didn’t stop child\n");
/*
* The child process has now stopped. Set its event flag indicating
* that it needs to trigger on a PTRACE_EXEC event.
*/
event_addr->pe_set_event = PTRACE_EXEC;
if (ptrace(PT_SET_EVENT_MASK, pid, event_addr, event_len))
printf("Parent: PT_SET_EVENT_MASK ptrace request failed\n");
if (pid != wait(&status)) /* wait failed */
printf("Parent: wait() failed with wrong wait status\n");
/*
* Send the child a message so it can break out of the while loop.
* Get it running so it can exec.
*/
write(filed[1], "now run", 7);
if (ptrace(PT_CONTIN, pid, 1, 0) != 0)
printf("Parent: failed to get child process running\n");
/*
* Wait for the traced child to stop after the exec system call in
* response to an exec event set in its ptrace_event structure.
*/
if (pid != (npid = wait(&status))) /* wait failed */
printf("Parent: wait() failed with wrong status\n");
if (!WIFSTOPPED(status))
printf("Parent: invalid wait() completion\n");
/*
* Child has stopped; fetch its process state and examine state
* information.
*/
if (ptrace(PT_GET_PROCESS_STATE, pid, state_addr, state_len) < 0)
printf("Parent: PT_GET_PROCESS_STATE ptrace request failed\n");
if (pid != wait(&status)) /* wait failed */
printf("Parent: wait() failed with wrong wait status\n");
/* Check if the pathlength value returned is non-zero */
if ((pathlength = state_addr->pe_path_len) == 0)
printf("Parent: zero length pathname returned\n");
/* Fetch exec’d file pathname and store it in the buffer. */
if (ptrace(PT_GET_PROCESS_PATHNAME, pid, buf_addr, (pathlength+1))
< 0){
printf("Parent: Failed to get exec pathname\n");
} else {
printf("Parent: the exec pathname is %s\n", buf_addr);
if (pid != wait(&status)) /* wait failed */
printf("Parent: wait() failed with wrong status\n");
}
}
HP-UX 11i Version 1: September 2005 − 6 − Hewlett-Packard Company Section 2−−259