c - Using Fork for Command Line Arguements -


i'm trying execute command "ls -l" i'm not sure how approach it.

this i've tried:

int main(void) {     char * input;     char * args[2];     char buff[100];      input = malloc(sizeof(buff));  while(fgets(input,sizeof(input),stdin) != null) {      printf("enter command\n");      if(strcmp(input,"ls -l\n") ==0) {         pid_t childpid;          childpid = fork();          if(childpid == 0) {             args[0] = "/bin/ls -l";             args[1] = null;              execv(args[0],args);     }  }  }  free(input); }

however, command doesn't seem work here. works if use "ls" want use "ls -l" there argument have pass work?

first have understand simple example.

#include <stdlib.h> #include <stdio.h> #include <string.h> #include <unistd.h> #include <sys/wait.h>  int main() {      /* status of child execution */     int status;     /* pointer * array of char*(strings)*/     char ** args;      /* allocate memory 3 char*(stings) */     args = (char**) malloc( 3 * sizeof(char*) );      /* fork program , store each fork id */     pid_t childpid = fork();      /* if child process */     if(childpid == 0) {          args[0] = "ls";         args[1] = "-l";         args[2] = null;          /* execute args[0] command args arguments */         execvp(args[0],args);          /* send execution code 0 parent , terminate child */         exit(0);      } else {          /* wait execution code child*/         wait(&status);          /* free allocated space */         free(input);         free(args);          /* exit program received code child */         exit(status);     }  }

i commented every line, tell me if want more informations. have understand how execute commands child , inform parent before continue user's input commands.


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