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Full Discussion: [Solved] Help piping tail to read STDIN
Top Forums Shell Programming and Scripting [Solved] Help piping tail to read STDIN Post 302444518 by Samb95 on Thursday 12th of August 2010 05:36:58 AM
Old 08-12-2010
MySQL
Quote:
Originally Posted by pludi
Are you sure that the regex is correct (I didn't test it)?
Other than that, you're printing without a newline at the end, so any output probably gets buffered. Either add a "\n" to the end, or disable output buffering by setting $| to 1.
Hi pludi,

Yes the regular expression is correct. It gives me exactly what I want, I have tested it. I will try to the "\n" at the end and let you know if it worked.
Thanks

---------- Post updated at 11:36 AM ---------- Previous update was at 10:58 AM ----------
Quote:
Originally Posted by pludi
Are you sure that the regex is correct (I didn't test it)?
Other than that, you're printing without a newline at the end, so any output probably gets buffered. Either add a "\n" to the end, or disable output buffering by setting $| to 1.
Sorry but, how do I do to say that the thread is solved ??

Hey pludi, it works. I would never had thought that a missing "\n" would cause the whole thing to not work.

Thanks a lot
 

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LEARN ABOUT CENTOS

tailf

TAILF(1)							   User Commands							  TAILF(1)

NAME

       tailf - follow the growth of a log file

SYNOPSIS

       tailf [OPTION] file

DESCRIPTION

       tailf will print out the last 10 lines of a file and then wait for the file to grow.  It is similar to tail -f but does not access the file
       when it is not growing.	This has the side effect of not updating the access time for the file, so a filesystem flush does not occur  peri-
       odically when no log activity is happening.

       tailf is extremely useful for monitoring log files on a laptop when logging is infrequent and the user desires that the hard disk spin down
       to conserve battery life.

       Mandatory arguments to long options are mandatory for short options too.

       -n, --lines=N, -N
	      output the last N lines, instead of the last 10.

       -V, --version
	      Output version information and exit.

       -h, --help
	      Display help and exit.

AUTHOR

       This program was originally written by Rik Faith (faith@acm.org) and may be freely distributed under the  terms	of  the  X11/MIT  License.
       There is ABSOLUTELY NO WARRANTY for this program.

       The latest inotify based implementation was written by Karel Zak (kzak@redhat.com).

SEE ALSO

       tail(1), less(1)

AVAILABILITY

       The tailf command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.

util-linux							   February 2003							  TAILF(1)
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