I am trying to save space on my client's unix box by compressing several files (each is at least 1 gig before compression). My problem is that I have a C program that uses these files, one at a time, as input. This program uses 'lseek' to find a particular location within the file, but this will present a problem once the files are compresses. Is lseek able to operate on a compressed file? If so, which method (compress, gzip, pack, etc...) is most compatible?