Here's the situation, I have an executable that gets info about a database (I didn't write it). When run from the shell it prints out a dozen lines describing database. Example:

Version
Release date:
Creation date: 2:17:09 AM EST Nov 19, 2004
Modified date: 2:17:09 AM EST Nov 19, 2004
Type: Nucleotide
Alphabet: NCBI2na(1)
No. of sequences (letters): 37,316 (33,115,935)
Longest sequence: 1542
Edit Alphabet: WUStLna(1)
Max. edits: 41
Total edits: 2693

I want a line in the middle that gives sequence count (in this example 37,316). I can gather the output with backticks and extract this number with some regular expression acrobatics, and store it in a variable easy enough. The problem is that everytime I execute the database info command, its output is automatically printed to the screen.

I don't want to see this output, I just want to run the script, have it gather the other program's output behind the scenes, and print out just the number. Is this even possible? I have tried a variety of ways of running the external program such as backticks, opening a pipe and using exec(), doing a manual fork() then exec(), and plain old system(). They all seem to work the same. Do I need to somehow filter my own STDOUT?

Thanks,
Jared

In reply to capture STDOUT without printing to screen by k99ja04

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