asked on

How do U do redirection?

How do I get this code to redirect the output of ls to list.txt
/*
      check for redirection
*/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>

int main()
{
      pid_t pid;
      int status;

      pid = fork();

      if (pid == 0)
      {
            int stdout = open ("list.txt", O_RDONLY);
            dup2 (stdout, STDOUT_FILENO);
            close (stdout);
            execl ("\\bin\\ls", "ls", NULL);
      }
      if (pid == -1)
            printf ("Error\n");
      else
            waitpid(pid, &status, 0);
}

baboo_

execl ("\\bin\\ls", "ls", , ">> list.txt", NULL);

maybe... I don't know if that's ok...

baboo_

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ozo

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van_dy

call to open() is wrong

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>

int main()
{
pid_t pid;
int status;

pid = fork();

if (pid == 0)
{
int stdout = open ("list.txt", O_WRONLY | O_CREAT); // use this
dup2 (stdout, STDOUT_FILENO);
close (stdout);
execl ("\\bin\\ls", "ls", NULL);
}
if (pid == -1)
printf ("Error\n");
else
waitpid(pid, &status, 0);
}