Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I ran the file command against a file and got this result:

data (gzip compressed data, was <fd:1> from unix)

What does the "<fd:1> from unix" mean?

share|improve this question
Whats the actual command that you executed? – ssapkota Jul 10 '11 at 14:06
up vote 3 down vote accepted

fd:1 is "file descriptor 1", which means standard output.

My guess is that the file is the result of a pipe from the output of another file like cat file|gzip - > new.gz

I was not able to reproduce that output, but it could be that different versions of gzip handle that differently.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.