zgrep, zegrep,
  zfgrep —
print lines matching a pattern in gzip-compressed files
  
    | zgrep | [grep-flags] [ --]
      pattern [files ...] | 
  
    | zegrep | [grep-flags] [ --]
      pattern [file ...] | 
  
    | zfgrep | [grep-flags] [ --]
      pattern [file ...] | 
zgrep runs
  grep(1) on
  files or stdin, if no files
  argument is given, after decompressing them with
  zcat(1).
The grep-flags and
    pattern arguments are passed on to
    grep(1). If an
    -e flag is found in the
    grep-flags, zgrep will not
    look for a pattern argument.
zegrep calls
    egrep(1), while
    zfgrep calls
    fgrep(1).
In case of missing arguments or missing pattern, 1 will be returned, otherwise
  0.
Thomas Klausner ⟨wiz@NetBSD.org⟩