Thread: Finding OS

Hi,

I am trying to write a C program that outputs the OS of the system. Does C have any functions that outputs the system properties. I didnot find any function which does this for me. Can anyone help me with this?

Chandana.

For Windows (all versions), the command is "ver".

Code:

system("ver");

Your C program must be somewhere in the path to the OS, for this to work. That would include the root of the boot drive, the Documents and Settings, and the Windows folders.

Linux has a similar command which I can't recall right off the bat.

Note that these are just OS commands, and not a part of C, itself.

For linux

system ("uname -a");

this should work on all unix and unix-likes. i dont know if windows has something similar to this.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h> 
#include <sys/utsname.h>

int main(int argc, char** argv)
{
	int SIZE=256;
     char Host[SIZE];
     struct utsname uts;

       
  if(gethostname(Host, SIZE) != 0 || uname(&uts) < 0)
  {
     fprintf(stderr, "%s\n",strerror(EINVAL));
             exit(1);
  }
  else
  {
        
			 fprintf(stdout,"%s\n%s\n", uts.sysname, uts.machine);
             fprintf(stdout,"%s\n%s\n",Host, uts.nodename);
             fprintf(stdout,"%s\n%s\n", uts.release, uts.version);
             
			 exit(0); 
        
   }
	return 0;
}

Originally Posted by MK27

Of course, that means you would have to already know what the OS is in order to use the right command.

You could check for the presence of certain "system specific commands" (such as ver or uname).

Also, I think there is some kind of #ifdef that can be used to detect windows, eg I have seen this used:

Code:

#ifdef WIN32
[....]
#else //assume linux
[...]
#endif

I'm pretty sure that is actually set by the compiler automatically on a win32 machine, but I could be wrong -- you'll have to check yerself.

each compiler differs in the OS Macro ...

Code:

#include <errno.h>
#include <unistd.h> 
#include <sys/utsname.h>

... I wonder if this works under Windows

Originally Posted by bvkim

Code:

#include <errno.h>
#include <unistd.h> 
#include <sys/utsname.h>

... I wonder if this works under Windows

it does not i guess. hence the attempt to get back to bed to avoid explaining why i did not read the tread before i posted properly .

Code:

#ifdef _WIN32
   #define OS "windows\n"
#include <windows.h>
#else
    #define OS "unix\n"
  #include <unistd.h> 
#include <sys/utsname.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

i ment to say something like this . (i think )
bedtime now ;=)

Thanks to all. Your suggestions have helped me a lot.

Chandana.