stat system call mode checking

ppy · 11-05-2004, 07:43 AM

Hello,

I am writing a part of the problem code : Can anybody tell me what is wrong in this code ?

if (st.st_mode != (S_IFCHR | S_IRUSR | S_IWUSR | S_IWGRP)) {

printf("Mode is not set for the device\n");
printf("Actual mode = %o\n",st.st_mode);
}
Is the comparison correct ?
mode of the device is 777.
printf always prints : Actual mode =0620 even if i change the mode of the device using chmod from command line.

Why is this ?

Regards,
ppy

itsme86 · 11-05-2004, 09:24 AM

Odd...it works for me:

Code:

#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>

int main(void)
{
  struct stat st;

  if(stat("testfile", &st) == -1)
  {
    perror("stat()");
    return 1;
  }

  printf("%o\n", st.st_mode & ~S_IFMT);
  return 0;
}

Code:

itsme@itsme:~/C$ touch testfile
itsme@itsme:~/C$ ls -l testfile
-rw-r--r--  1 itsme users 0 2004-11-05 07:23 testfile
itsme@itsme:~/C$ ./mode
644
itsme@itsme:~/C$ chmod 0600 testfile
itsme@itsme:~/C$ ls -l testfile
-rw-------  1 itsme users 0 2004-11-05 07:23 testfile
itsme@itsme:~/C$ ./mode
600