A program on UNIX-like operating systems which tells you information about the box you're on. Here's mine:

$ uname -a
Linux tftv 2.4.0-test9 #1 Tue Oct 3 17:25:35 EDT 2000 i686

That means my kernel is Linux 2.4.0-test9 compiled on Tuesday October 3, 2000 at 17:25:35 EDT, I'm running an i686, and my host name is tftv.

Okay, so now here's my little quick rewrite of "uname -a" to demonstrate the system call by the same name:

#include <stdio.h>
#include <sys/utsname.h>

int main() {

   struct utsname uname_struct;
   uname( &uname_struct );

   printf( "%s %s %s %s\n", uname_struct.sysname, uname_struct.nodename,
                            uname_struct.release, uname_struct.machine );

   return 0;

Yeah, I'm pretty bored to be writing this. :)