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) User Commands 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.
-c, --bytes=[+]NUM
output the last NUM bytes; or use -c +NUM to output starting with byte NUM of each file
-f, --follow[={name|descriptor}]
output appended data as the file grows;
an absent option argument means 'descriptor'
-F same as --follow=name --retry
-n, --lines=[+]NUM
output the last NUM lines, instead of the last 10; or use -n +NUM to output starting with line NUM
--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);
with inotify, this option is rarely useful
--pid=PID
with -f, terminate after process ID, PID dies
-q, --quiet, --silent
never output headers giving file names
--retry
keep trying to open a file if it is inaccessible
-s, --sleep-interval=N
with -f, sleep for approximately N seconds (default 1.0) between iterations; with inotify and --pid=P, check process P at least once
every N seconds
-v, --verbose
always output headers giving file names
-z, --zero-terminated
line delimiter is NUL, not newline
--help display this help and exit
--version
output version information and exit
NUM may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T,
P, E, Z, Y.
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 in a way that accommodates renaming,
removal and creation.
AUTHOR
Written by Paul Rubin, David MacKenzie, Ian Lance Taylor, and Jim Meyering.
REPORTING BUGS
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Report tail translation bugs to <http://translationproject.org/team/>
COPYRIGHT
Copyright (C) 2017 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
head(1)
Full documentation at: <http://www.gnu.org/software/coreutils/tail>
or available locally via: info '(coreutils) tail invocation'
GNU coreutils 8.28 January 2018 TAIL(1)