You could try approaching the problem from a different angle

Code:
D:\code>print /?
Prints a text file.

PRINT [/D:device] [[drive:][path]filename[...]]

   /D:device   Specifies a print device.
Now the print command can be used to print a text file. Rather than changing your program, I would suggest some experiments with the print command to see if you can actually print anything.

Something else to look at
> if((printer = fopen("LPT1","w")) == NULL)
Do you have a file called "LPT1" in your directory?