1 files changed, 59 insertions, 0 deletions
diff --git a/semestr-5/so/lista2/so21_lista_2/reaper.c b/semestr-5/so/lista2/so21_lista_2/reaper.c
new file mode 100644
index 0000000..da43a2f
--- /dev/null
+++ b/semestr-5/so/lista2/so21_lista_2/reaper.c
@@ -0,0 +1,59 @@
+#include "csapp.h"
+
+static pid_t spawn(void (*fn)(void)) {
+  pid_t pid = Fork();
+  if (pid == 0) {
+    fn();
+    printf("(%d) I'm done!\n", getpid());
+    exit(EXIT_SUCCESS);
+  }
+  return pid;
+}
+
+static void grandchild(void) {
+  printf("(%d) Waiting for signal!\n", getpid());
+  pause();
+  printf("(%d) Got the signal!\n", getpid());
+}
+
+static void child(void) {
+  pid_t pid;
+  setpgid(0, 0);
+  pid = spawn(grandchild);
+  printf("(%d) Grandchild (%d) spawned!\n", getpid(), pid);
+}
+
+/* Runs command "ps -o pid,ppid,pgrp,stat,cmd" using execve(2). */
+static void ps(void) {
+  pid_t pid = Fork();
+  if (pid == 0) {
+    if (execlp("ps", "ps", "-o", "pid,ppid,pgrp,stat,cmd", NULL) < 0) {
+      fprintf(stderr, "Exec error: %s\n", strerror(errno));
+      exit(EXIT_FAILURE);
+    }
+  }
+  waitpid(pid, NULL, 0);
+}
+
+int main(void) {
+  /* TODO: Make yourself a reaper. */
+#ifdef LINUX
+  Prctl(PR_SET_CHILD_SUBREAPER, 1);
+#endif
+  printf("(%d) I'm a reaper now!\n", getpid());
+
+  pid_t pid, pgrp;
+  int status;
+
+  /* TODO: Start child and grandchild, then kill child!
+   * Remember that you need to kill all subprocesses before quit. */
+  pid = spawn(child);
+  pgrp = pid;
+  waitpid(pid, &status, 0);
+  ps();
+
+  Kill(-pgrp, SIGINT);
+  pid = wait(&status);
+  printf("Reaped the grandchild (%d), exit code: %d\n", pid, status);
+  return EXIT_SUCCESS;
+}