Add quiz/run

Author: lasyard

quiz/CMakeLists.txt

@@ -17,4 +17,5 @@ add_exe(eight_queen eight_queen.c)
 add_exe(horse_move horse_move.c)
 add_exe(logic_question logic_question.c)
 add_exe(nine_interlocking_rings nine_interlocking_rings.c)
+add_exe(run run.c)
 add_exe(sudoku sudoku.c)

quiz/run.c

@@ -0,0 +1,44 @@
+#include <errno.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/wait.h>
+
+static void log_err(const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    vfprintf(stderr, fmt, args);
+    fputc('\n', stderr);
+    va_end(args);
+}
+
+static bool run_cmd(int argc, char *argv[])
+{
+    if (argc < 2) {
+        log_err("No command given");
+        return false;
+    }
+    pid_t pid = fork();
+    if (pid < 0) {
+        log_err("Cannot run command: fork failed: %s", strerror(errno));
+        return false;
+    } else if (pid == 0) {
+        /* Generally the first argument is itself, so skip it */
+        if (execvp(argv[1], &argv[1]) < 0) {
+            log_err("Cannot run command: %s", strerror(errno));
+        }
+        exit(EXIT_FAILURE);
+    }
+    return true;
+}
+
+int main(int argc, char *argv[])
+{
+    run_cmd(argc, argv);
+    wait(NULL);
+}