06-20-2012
Redirecting stdout problem
I have a simple bash script that prints sth every 5 seconds. What I do is the following. I redirect the output of the script to a file, tail the file and see that it works and then from another console I delete the file where the output is redirected to. Even though I have deleted the file, the tail still works. Stoping the tail and starting it again of course fails because the file is not found.
My question is whether this is normal and does the output go "somewhere" after deleting the file where it is supposed to be redirected.
Best,
Iliya
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TAIL(1) FSF TAIL(1)
NAME
tail - output the last part of files
SYNOPSIS
tail [OPTION]... [FILE]...
DESCRIPTION
Print the last 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With
no FILE, or when FILE is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
--retry
keep trying to open a file even if it is inaccessible when tail starts or if it becomes inaccessible later -- useful only with -f
-c, --bytes=N
output the last N bytes
-f, --follow[={name|descriptor}]
output appended data as the file grows; -f, --follow, and --follow=descriptor are equivalent
-F same as --follow=name --retry
-n, --lines=N
output the last N lines, instead of the last 10
--max-unchanged-stats=N
with --follow=name, reopen a FILE which has not changed size after N (default 5) iterations to see if it has been unlinked or
renamed (this is the usual case of rotated log files)
--pid=PID
with -f, terminate after process ID, PID dies
-q, --quiet, --silent
never output headers giving file names
-s, --sleep-interval=S
with -f, sleep for approximately S seconds (default 1.0) between iterations.
-v, --verbose
always output headers giving file names
--help display this help and exit
--version
output version information and exit
If the first character of N (the number of bytes or lines) is a `+', print beginning with the Nth item from the start of each file, other-
wise, print the last N items in the file. N may have a multiplier suffix: b for 512, k for 1024, m for 1048576 (1 Meg).
With --follow (-f), tail defaults to following the file descriptor, which means that even if a tail'ed file is renamed, tail will continue
to track its end. This default behavior is not desirable when you really want to track the actual name of the file, not the file descrip-
tor (e.g., log rotation). Use --follow=name in that case. That causes tail to track the named file by reopening it periodically to see if
it has been removed and recreated by some other program.
AUTHOR
Written by Paul Rubin, David MacKenzie, Ian Lance Taylor, and Jim Meyering.
REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.
COPYRIGHT
Copyright (C) 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
LAR PURPOSE.
SEE ALSO
The full documentation for tail is maintained as a Texinfo manual. If the info and tail programs are properly installed at your site, the
command
info tail
should give you access to the complete manual.
tail (coreutils) 4.5.3 February 2003 TAIL(1)