*NIX systems programming: error using stat function

MDBlueIce · 06-24-2005, 08:33 AM

Can someone who is familiar with the

int stat(const char *restrict path, struct stat *restrict buf)

function in C tell me why the following code does not output "succesful"?

int main()
{

struct stat * buf;
if (lstat("/bin/ls", buf)==0)
printf("succesful\n");

}

Thankyou.

MoneyCat · 06-24-2005, 08:51 AM

Code:

      1 #include <sys/stat.h>
      2
      3 int main()
      4 {
      5     struct stat buf;
      6
      7     if (lstat("/bin/ls", &buf)==0)
      8         printf("succesful\n");
      9
     10     return 0;
     11
     12 }

The only change from your code is that you were passing an incorrect parameter to lstat.

Good Luck

MDBlueIce · 06-24-2005, 09:09 AM

Your code gives me the following compilation error on line 5:

error: storage size of 'buf' isn't known

Were you able to compile it yourself?

MoneyCat · 06-24-2005, 09:15 AM

Quote:

Were you able to compile it yourself?

Yes, it compiled & gave a 'successful' output on:

1) Ubuntu 5.04 -- gcc v3.3.5
2) IRIX64 Neptune -- gcc v2.95.3
3) IRIX64 Neptune -- MIPSPro v7.4

That errors seems to indicate that the compiler was unable to find struct stat in the sys/stat.h header file.

MDBlueIce · 06-24-2005, 10:34 AM

Well. I'm compiling it on cygwin in the office. Perhaps when I go home I will try it on a true *NIX installation, Slackware. Thanks for the help though.

MoneyCat · 06-24-2005, 10:51 AM

Quote:

Well. I'm compiling it on cygwin in the office.

Well, your thread does say "*NIX systems programming..."

itsme86 · 06-24-2005, 10:59 AM

According to man stat you should be #include'ing all these:

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

That could very likely be your problem.

MDBlueIce · 06-27-2005, 06:42 AM

Yes, you were right. The extra
#include <sys/stat.h>
allowed my coed to compile. Thankyou.