10-23-2002
try using
tail -f log_X | grep n >> log_Y
I'm not sure this would work...
I can add that the commands on either side of a pipe "|" are started and executed synchronously... and we know that any command like grep will finish only if it sees an EOF, which "tail -f" will not give as it is in an infinite loop looking for newly appended lines...
so...
tail -f log_X | grep n
should be working fine and giving "new" lines having "n" to stdout as and when they append to log_x...
It may be a problem with redirection, so use redirection in append mode >> and let us know!!
Cheers!
Vishnu.
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LEARN ABOUT NETBSD
zfgrep
ZGREP(1) BSD General Commands Manual ZGREP(1)
NAME
zgrep, zegrep, zfgrep -- print lines matching a pattern in gzip-compressed files
SYNOPSIS
zgrep [grep-flags] [--] pattern [files ...]
zegrep [grep-flags] [--] pattern [file ...]
zfgrep [grep-flags] [--] pattern [file ...]
DESCRIPTION
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).
EXIT STATUS
In case of missing arguments or missing pattern, 1 will be returned, otherwise 0.
SEE ALSO
egrep(1), fgrep(1), grep(1), gzip(1), zcat(1)
AUTHORS
Thomas Klausner <wiz@NetBSD.org>
BSD
December 28, 2003 BSD