Question

I have a server program just writes output log to STDOUT.
I also have another Perl shell script named “logfile” ,it will gets data from STDIN and shows some output.

linux$ server |  logfile

at first log-file has output ,but after a few moments it stops..
is there anyone has came across this problem?

Answer 1

server probably buffers its output, feeding it to the pipe in chunks. Is server a Perl script? Add

$| = 1;

or

use Handle qw( );
STDOUT->autoflush(1);

to it to disable buffering for STDOUT. (Well, the first one will disable buffering for whatever handle you have selected, but that’s STDOUT by default.)