making a shell with C

Question

i am trying to create a shell using C as a homework but my execvp() doesnt work . it doesnt exe the ls. i am working at a virtual machine lubuntu 32 Thas my outpout any my error message !

if(pid==0){        
       printf("child");                                                                                                            
  char **tokens=tokenizer(hey)//hey is from fgets. tokenizer is fine
printer(tokens);

  //execute ls                                                                                                                                                               
  execvp( ls_args[0], ls_args);

  //only get here if exec failed                                                                                                                                             
  perror("execv failed");

  return 2; //return error status   }

Why are you hiding the error message from us? Is this some kind of trick or prank? It's clearly information that you *have*, so what good could there possibly be in this partial information? — Kerrek SB, Apr 16 '15 at 20:54
it doesnt showing any error message its just print "child" and my program continues working till the parent proccess ends. if i do execlp("ls","ls","-l",NULL); its working ! — Panos, Apr 16 '15 at 20:57
is `ls` in the path of whatever shell you're using? maybe it should be `/bin/ls` instead. — Marc B, Apr 16 '15 at 20:57
@user3135218: In that case, execvp is not failing, since it never returns. This is a problem with `ls`. Is the working directory empty? — Kevin, Apr 16 '15 at 20:59
@kevin i got my source file at working directory its not empty :( — Panos, Apr 16 '15 at 21:02
Include the error in your post, people viewing this aren't all going to read the comments. — ShellFish, Apr 16 '15 at 22:20

score 1 · Accepted Answer · answered Apr 17 '15 at 12:07

1

Your third argument (a[2]) has a newline character at the end. ls thus complains that it can't find a directory named with a single newline character under your home directory. Fix your command parsing to not include the newline.

answered Apr 17 '15 at 12:07

Dark Falcon

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its doing the same with ls – Panos Apr 17 '15 at 14:31
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Please learn to be more descriptive. Tell EXACTLY what you did and what happened. – Dark Falcon Apr 17 '15 at 14:35
i changed it take a loook – Panos Apr 22 '15 at 15:38

making a shell with C

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