c - how to execute a command as root -

i develop c code on linux (debian). time time, need execute commands through system()

i wonder if possible execute command via system()as root. if not case, there function execute command (or run binary) root can use on c code?

we met situation before want execute root command normal user, here our solution (using setuid/suid):

assume that:

• username: tom
• group: gtom
• c program file: my_pro.c

step 1: write c code tool: my_sudo.c

... int main(int args, char *argv[]) {     if (args < 2)          printf("usage: my_sudo [cmd] [arg1 arg2 ...]");      // cmd here shell cmd want execute in "my_pro"     // can check shell cmd privilege here     // example:  if (argv[1] != "yum") return; allow yum execute here      char cmd[max_cmd];     int i;     ( = 2; < args; ++) {     // concatenate cmd, example: "yum install xxxxx"         strcat(cmd, " ");         strcat(cmd, argv[i]);     }      system(cmd); }  

step 2: compile my_sudo.c my_sudo executable file

   sudo chown root:gtom my_sudo   // user root && gtom group    sudo chmod 4550 my_sudo        // use suid root privilege     #you see my_sudo this(ls -l)    #-r-sr-x--- 1 root my_sudo 9028 jul 19 10:09 my_sudo*     #assume put my_sudo /usr/sbin/my_sudo 

step 3: in c code

... int main() {     ...     system("/usr/bin/mysudo yum install xxxxx");     ... }  #gcc && ls -l #-rwxr--r--  1 tom gtom 1895797 jul 23 13:55 my_pro 

step 4: execute./my_pro

you can execute yum install without sudo.