exec_file.c

AnimalProcessing/Fundamentals/exec.c

@@ -0,0 +1,45 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <err.h>
+
+int execute_me(char *cmd, char **argv){
+
+    if (!cmd || !argv || !*argv) return 1;
+    
+    int wstatus;
+
+    pid_t pid = fork();
+
+    if (pid < 0) return -1;
+
+    // Child
+    else if (pid == 0) {
+
+           if (cmd != *argv) exit(-1);
+           else exit(execvp(cmd, argv));
+    }
+
+    // Daddy
+    else {
+
+        if(waitpid(pid, &wstatus, 0) == -1) return -1;
+
+        if(WIFEXITED(wstatus)) return WEXITSTATUS(wstatus);
+        
+        return 0;
+    }
+
+}
+/*
+int main(){
+    char *argv[] = {"ls", "-l", NULL};
+int r1 = execute_me("ls", argv);
+printf("%d\n", r1);
+
+    int r2 = execute_me("wrong", argv);
+    printf("%d\n", r2);
+}*/

AnimalProcessing/Fundamentals/exec_file.c

@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <err.h>
+
+int execute_me2(char *file, char **args){
+
+    if(!file || !args || !*args) return 1;
+
+    int wstatus;
+    pid_t pid = fork();
+
+    if (pid < 0) return -1;
+
+    // Child
+    else if (pid == 0) {
+
+        if(file != *args) exit(-1);
+
+        exit(execlp(file, args[0], args[1], (char *)NULL));
+    }
+
+    // Daddy
+    else {
+        
+        if(waitpid(pid, &wstatus, 0) ==  -1) return -1; 
+
+        if(WIFEXITED(wstatus)) return WEXITSTATUS(wstatus);
+    }
+    return 0;
+}
+/*
+int main(){
+char *argv[] = {"ls", "-l", NULL};
+execute_me2("ls", argv);                 // should be the same as doing "ls -l" in the shell
+
+//char *argv[] = {"ls", "-l", NULL};
+int i = execute_me2("wrong", argv);              // should return 255
+}*/