simple pipe question

[ggggus]

I'm a relative newbie trying to understand the pipe.

I've got a gzip'ed log file that I want to run a couple of commands on...sure I could run them all seperately, but I'm trying to run them from a php application...and more importantly, I'm trying to learn new stuff here....so here's what I've got.

gzip -d php_error_log.1.gz | tac > temp.log

But that doesn't work...it unzips the log file and creates a blank temp.log file. Can someone tell me how to do what I'm trying to do in one line?

***************************************
J. Jacobs

http://www.piercedmedia.com

 

[ggggus]

I figured it out...the problem wasn't my use of the pipe... I needed a -c on the gzip command.

***************************************
J. Jacobs

http://www.piercedmedia.com

 

[victorv]

hi,
not all programs are "pipeable", it depends how they are written, and how are managed stdin,out,err.
The more program or sort are pipeable.
Pipe is a "automation" tool: does in a just 1 (apparent) command what you can do in different steps: he creates temporary files (in var dir) and at the end of single command, thos fole are deleted. However in our
jobs, you have a system (a command, a computer, or other)
that does not go, you must have the ability to segment
the system and invividuate which is the sector that is responsible of malfunctioning.

Then try 1st

1) gzip -c -d php_error_log.1.gz > php_error_log.1
2) tac php_error_log.1 > error.log
or
tac php_error_log.1 | more
ecc

Using this approach you'll find becouse you have to use -c option as suggested by yourself

to reach
gzip -c -d php_error_log.1.gz | tac > temp.log