Execute binary from C++ without shell -


is there way execute binary c++ program without shell? whenever use system command gets run via shell.

you need to:

  1. fork process
  2. call 1 of "exec" functions in child process
  3. (if necessary) wait stop

for example, program runs ls. 

#include <iostream>  #include <unistd.h> #include <sys/wait.h>  // example, let's "ls" int ls(const char *dir) {    int pid, status;    // first fork process    if (pid = fork()) {        // pid != 0: parent process (i.e. our process)        waitpid(pid, &status, 0); // wait child exit    } else {        /* pid == 0: child process. let's load           "ls" program process , run */         const char executable[] = "/bin/ls";         // load it. there more exec__ functions, try 'man 3 exec'        // execl takes arguments parameters. execv takes them array        // execl though, so:        //      exec         argv[0]  argv[1] end        execl(executable, executable, dir,    null);         /* exec not return unless program couldn't started.            when child process stops, waitpid() above return.        */      }    return status; // parent process again. }   int main() {     std::cout << "ls'ing /" << std::endl;    std::cout << "returned: " << ls("/") << std::endl;     return 0; }

and output is:

ls'ing / bin   dev  home        lib    lib64       media  opt   root  sbin     srv  tmp  var boot  etc  initrd.img  lib32  lost+found  mnt    proc  run   selinux  sys  usr  vmlinuz returned: 0

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