how to connect printer to the c program output ?

Ha! this is the myth of 'high level' languages.
Use the 'printf' function, but of course if you are writing for your own non standard harware you will have to write your own printer driver in a low level language.
Del

PRINTF FUNCTION MEANS LIKE HOW ?ANY EXAMPLE.... WHICH OUTPUT IS OBTAINED IN HARDCOPY

im using window xp and shared printer .. so i dont know to how to code

fprintf(stdprn,"hello");

stdprn = fopen("PRN","wb");
fprintf(stdprn,"From Windows: Test test test\f");
fclose(stdprn);

i used this code

IN my system im using shared printer and port connected is DOT4_001

i didt get any response from printer while compiling

Sorry can't help, this is way out of my experience. I code small control systems with hardware designed by me. People occasionally say they want our stuff to interface to a laptop.
They don't really need it, and why would I want to design a load of hardware and write code so that Bill Gates can make it obsolete a year down the road?
In the old days you could just output to the printer port or serial of a PC via a quick knife and fork program in QBasic in 5 minutes. They call this progress.
Del

hmmm thank u sir

Hyuk yuk yuk!

i got output by coverting output into txt