Add third_party/pexpect

third_party/pexpect/tests/platform_checks/CSIGNALTEST/test.c

+/* I built this with "gcc -lutil test.c -otest" */
+#include <sys/types.h>  /* include this before any other sys headers */
+#include <sys/wait.h>   /* header for waitpid() and various macros */
+#include <signal.h>     /* header for signal functions */
+#include <stdio.h>      /* header for fprintf() */
+#include <unistd.h>     /* header for fork() */
+#ifdef LINUX
+#include <pty.h>
+#else
+#include <util.h>       /* header for forkpty, compile with -lutil */
+#endif
+
+void sig_chld(int);  /* prototype for our SIGCHLD handler */
+
+int main() 
+{
+    struct sigaction act;
+    int pid;
+    int fdm;
+    char slave_name [20];
+
+
+    /* Assign sig_chld as our SIGCHLD handler.
+       We don't want to block any other signals in this example 
+       We're only interested in children that have terminated, not ones
+       which have been stopped (eg user pressing control-Z at terminal).
+       Finally, make these values effective. If we were writing a real 
+       application, we would save the old value instead of passing NULL.
+     */
+    act.sa_handler = sig_chld;
+    sigemptyset(&act.sa_mask);
+    act.sa_flags = SA_NOCLDSTOP;
+    if (sigaction(SIGCHLD, &act, NULL) < 0) 
+    {
+        fprintf(stderr, "sigaction failed\n");
+        return 1;
+    }
+
+    /* Do the Fork thing. 
+    */
+    pid = forkpty (&fdm, slave_name, NULL, NULL);
+    /* pid = fork(); */
+
+    switch (pid)
+    {
+            case -1:
+                fprintf(stderr, "fork failed\n");
+                return 1;
+            break;
+
+            case 0: /* Child process. */     
+                printf ("This child output will cause trouble.\n");
+                _exit(7);
+            break;
+
+            default: /* Parent process. */
+                sleep(1);
+                printf ("Child pid: %d\n", pid); 
+                sleep(10);  /* let child finish -- crappy way to avoid race. */
+            break;
+    }
+
+    return 0;
+}
+ 
+void sig_chld(int signo) 
+{
+    int status, wpid, child_val;
+
+    printf ("In sig_chld signal handler.\n");
+
+    /* Wait for any child without blocking */
+    wpid = waitpid (-1, & status, WNOHANG);
+    printf ("\tWaitpid found status for pid: %d\n", wpid);
+    if (wpid < 0)
+    {
+        fprintf(stderr, "\twaitpid failed\n");
+        return;
+    }
+    printf("\tWaitpid status: %d\n", status);
+
+    if (WIFEXITED(status)) /* did child exit normally? */
+    {
+        child_val = WEXITSTATUS(status); 
+        printf("\tchild exited normally with status %d\n", child_val);
+    }
+    printf ("End of sig_chld.\n");
+}
+
+