since command

Unix tail tail command is a standard way of watching log files in Unix. There is also less well known, but more useful utility called since which is distributed with Cygwin package and can be compiled on any Unix platform.  It is capable remembering the last line of the file viewed so only new lines are displayed.

since - display content of a file since the last time

since [-hnqvx] files

DESCRIPTION

since is similar to tail since it also displays the tail of a file. However since displays only the data which has been added since the last time since was run. If since has not been run before the entire file is displayed. since is useful for watching over log files.

EXAMPLE

since /var/log/apache/{access,error}_log > /dev/null
lynx --dump http://localhost/ > /dev/null
since /var/log/apache/{access,error}_log

OPTIONS

• -h Print a terse help message.
• -n Do not update the .since file which keeps track of file growth.
• -q Decrease the verbosity of the output.
• -v Increase the verbosity of the output.
• -x Exclude files with compressed extensions.

FILES

.since

File recording the length of the files displayed previously. The location of the file can be set by using the SINCE environment variable, for example export SINCE= /var/log/sincefile will tell since to use the file /var/log/sincefile. If the SINCE environment variable has not been set since will use the HOME environment variable and store the information in the file .since in the directory pointed to by the variable. If neither the SINCE nor the HOME variable are set since will use the file /tmp/since.
 

BUGS

since will break when used across NFS on architectures which have different st_* field sizes. since uses the inode of a file as its key, if that inode is recycled since might get confused. since is not particularly efficient when storing the stat() information, but should work reasonably well unless you plan to look at thousands of files. Functionality equivalent to since can probably be achieved with a number of trivial shell scripts.

COPYING
since may only be used, distributed and modified in accordance with the terms of the GPL (GNU General Public License) as published by the FSF (Free Software Foundation).

SEE ALSO
tail(1), stat(2).

Linux JULY 1998 SINCE(1)

NEWS CONTENTS

• 20100127 : SINCE(1) ( Jan 27, 2010 )
• 20100127 : MultiTail ( MultiTail, )
• 20100127 : inotail ( inotail, )
• 20100127 : 2007-09-07 - inotail 0.5 released ( )
• 20100127 : tail ( tail, )
• 20100127 : PPT tail ( PPT tail, )
• 20100127 : Perl Tail ( Perl Tail, )
• 20100127 : The tail Command ( The tail Command, )
• 20100127 : freshmeat.net Project details for inotail ( freshmeat.net Project details for inotail, )
• 20100127 : TTTT head and tail ( TTTT head and tail, )
• 190317 : RPM Search since ( RPM Search since, )
• 190317 : since for AIX ( since for AIX, )
• 190317 : Index of -ubuntu-pool-universe-s-since ( Index of -ubuntu-pool-universe-s-since, )

Old News ;-)

[Jan 27, 2010] SINCE(1)

This very useful utility is distributed with Cygwin.

since - display content of a file since the last time

since [-hnqvx] files

DESCRIPTION

since is similar to tail since it also displays the tail of a file. However since displays only the data which has been added since the last time since was run. If since has not been run before the entire file is displayed. since is useful for watching over log files.

EXAMPLE

since /var/log/apache/{access,error}_log > /dev/null
lynx --dump http://localhost/ > /dev/null
since /var/log/apache/{access,error}_log

OPTIONS

• -h Print a terse help message.
• -n Do not update the .since file which keeps track of file growth.
• -q Decrease the verbosity of the output.
• -v Increase the verbosity of the output.
• -x Exclude files with compressed extensions.

FILES

.since

File recording the length of the files displayed previously. The location of the file can be set by using the SINCE environment variable, for example export SINCE= /var/log/sincefile will tell since to use the file /var/log/sincefile. If the SINCE

MultiTail

MultiTail lets you view one or multiple files like the original tail program. The difference is that it creates multiple windows on your console (with ncurses). It can also monitor wildcards: if another file matching the wildcard has a more recent modification date, it will automatically switch to that file. That way you can, for example, monitor a complete directory of files. Merging of 2 or even more logfiles is possible. It can also use colors while displaying the logfiles (through regular expressions), for faster recognition of what is important and what not. It can also filter lines (again with regular expressions). It has interactive menus for editing given regular expressions and deleting and adding windows. One can also have windows with the output of shell scripts and other software.

When viewing the output of external software, MultiTail can mimic the functionality of tools like 'watch' and such.
For a complete list of features, look here.

inotail

inotail is a replacement for the 'tail' program found in the base installation of every Linux/UNIX system. It makes use of the inotify infrastructure in recent versions of the Linux kernel to speed up tailing files in the follow mode (the '-f' option). Standard tail polls the file every second by default while inotail listens to special events sent by the kernel through the inotify API to determine whether a file needs to be reread.

Currently inotail is not fully compatible to neither POSIX or GNU tail but might be in the future. (Note: I'm currently working on correct tailing from pipes which would make inotail fully compatible to POSIX tail)

• Linux kernel 2.6.13 or higher with CONFIG_INOTIFY enabled
• Standard C Library (tested with GNU libc but might work with others too)

2007-09-07 - inotail 0.5 released

Released version 0.5 of inotail containing only small fixes. Please refer to the changelog for details.

download

• inotail-0.5.tar.gz
• inotail-0.5.tar.bz2

• md5sums (for all releases)
• sha1sums (for all releases)

Debian users can find the inotail package in the Debian package archive. inotail is also available in the Ubuntu Universe repository.

PPT tail

#!/usr/bin/perl -w

#
# A Perl implementation of tail for the Perl Power Tools project by
# Thierry Bézecourt <[email protected]>. Includes an implementation
# of Chip Rosenthal's xtail.
#
# Please see the pod documentation at the end of this file.
#
# 99/12/24 : made tail -f work on VMS (thanks to Joe Kazimierczyk)
# fixed a bug when tailing small files
# 99/11/19 : important performance improvement for tail on big files
# (now usable for any file size)
# 99/03/07 : implemented xtail in the -f option
# 99/03/03 : fixed the -f option which was completely broken
# 99/03/02 : first version

PPT tail

This is the homepage for the Perl Power Tools implementation of the standard tail command.

Current Perl implementations are:

• Here is a version and its manpage by Thierry Bezecourt (1999-03-07).
  Supporting files: readme.thierry, mktest.thierry.

Baseline documentation:

• Version 7
• BSD (with POSIX.2 info, if relevant)

Perl Tail

#!/usr/bin/perl

use File::Tail;
$file=File::Tail->new( $file_to_tail );
while (defined($line=$file->read))
{
print $line;
}

The tail Command

The output from other commands can be piped (i.e., sent) to tail to use as its input. For example, the following sends the output from the ls command (which by default lists the names of the files and directories in the current directory) to tail, which, in turn, prints the final ten lines of the output that it receives from ls to the monitor screen:

ls | tail

This output could easily be redirected, for example to a file named last_filenames as follows:

ls | tail >> last_filenames

It could also be piped to one or more filters for additional processing. For example, the sort filter could be used with its -r option to sort the output in reverse alphabetic order prior to writing to a file:

ls | tail | sort -r >> last_filenames

The -q (i.e., quiet) option causes tail to not print the file name before each set of lines and to eliminate the vertical space between each set of lines when there are multiple input sources. The -v (i.e., verbose) option causes tail to print the file name even if there is just a single input file.

Tail could be viewed as a counterpart of the head command, which always starts reading from the beginning of files and which can continue until any specified distance from the beginning. However, there are a few differences. Perhaps the most useful of these is that tail is somewhat more flexible in that, in addition to being able to start reading any specified distance from the end of a file, it can also start at any specified distance from the beginning of a file.

Tail can be instructed to begin printing from some number of lines or bytes from the start of a file by preceding the number with a plus sign instead of a minus sign. For example, the following would print each of the designated files to the display monitor beginning with the seventh line and until the end:

tail +7 aardvark anteater armadillo

The c option could be used to tell tail to print each of the designated files beginning with the seventh byte instead of the seventh line:

tail +7c aardvark anteater armadillo

freshmeat.net Project details for inotail

inotail is a replacement for the 'tail' program found in the base installation of every Linux/Unix system. It makes use of the inotify infrastructure in recent versions of the Linux kernel to speed up tailing files in the follow mode (the '-f' option). Standard tail polls the file every second by default, while inotail listens to special events sent by the kernel through the inotify API to determine whether a file needs to be reread.

TTTT head and tail

Similarly, tail shows the last few lines (again, 10 by default) of a file or stream:

---

% ypcat passwd | tail
cal:*:1492:160:Calvin Hobbes:/home/cal:/bin/csh
adams:*:116:100:John Adams:/home/pkduck-b/adams:/bin/csh
gary:*:1177:20:Gary North:/home/pkduck-e/gary:/bin/csh
quincy:*:1092:20:Quincy Lizard:/home/triton-a/quincy:/bin/csh
talbot:*:1679:75:Bob Talbot:/home/enterprise-a/cadmec/talbot:/bin/csh
help:*:1034:31:Help Desk:/home/lewey-a/processor/help:/bin/csh
glen:*:1543:20:Glen Carpenter:/home/pkduck-e/glen:/bin/csh 
brent:*:1799:706:Brent Adams:/home/dogbert-a/brent:/bin/csh
lou:*:1701:30:Lou Grant:/home/pkduck-h/lou:/bin/csh 
adam:*:1124:317:Adam Baker:/home/lewey-d/adam:/bin/csh

---

As with head, you can specify the number of lines from the end of the file at which to start display by prefacing the number with a hyphen ("-"). You can also specify the location as a number of lines from the beginning by prefacing the number with a plus sign ("+"):

---

% wc -l /usr/man/man1/tail.1
     143 /usr/man/man1/tail.1
% tail +141 /usr/man/man1/tail.1
.LP
Various kinds of anomalous behavior may happen with character special
files.
% tail -3 /usr/man/man1/tail.1
.LP
Various kinds of anomalous behavior may happen with character special
files.

---

Since the tail man page has 143 lines, "tail +141" is equivalent to "tail -3" in this case.

Unlike with head, tail will operate on units other than lines. By adding the character "b" to the number, you can display the last blocks, and with "c" the last characters:

---

% tail -10c /usr/man/man1/tail.1
al
files.

---

Don't forget about newlines.

tail also has the unexpected function that it allows you to reverse the lines spewed. By default, with just the "-r" flag, tail displays the whole file in reverse order by line:

---

% cat > foo << END
this
is
a
test
END
% tail -r foo
test
a
is
this

---

A number of lines to reverse can be included, but it cannot be relative to the beginning of the file, only the end. ("+" acts just like "-")

tail also has the wildly useful feature that it can be told to wait around for further input to a file rather than stopping when it gets to the end. This is especially useful to monitor the progress of a process whose output you have redirected to a file:

---

% clearmake >& Transcript &
[1] 12688
% tail -f Transcript

[the output from the clearmake will be displayed here as it arrives in "Transcript"]

---

When called in this manner, the tail will continue to read lines from the file and wait for more until you kill it ("^C" is handy here ;-) even after the clearmake has completed and there is no longer output being appended to the file.

One final difference between head and tail: while head will operate on multiple files, tail will not, so don't expect something like "tail foo bar biff" to show anything more than the last 10 lines of "foo".

RPM Search since

OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_Factory/i586/since-0.5-2.70.i586.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_Factory/x86_64/since-0.5-2.34.x86_64.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_11.0/x86_64/since-0.5-2.1.x86_64.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_10.3/x86_64/since-0.5-2.1.x86_64.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/SLE_10/x86_64/since-0.5-2.1.x86_64.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/SLE_10/i586/since-0.5-2.1.i586.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_11.0/i586/since-0.5-2.1.i586.rpm
OpenSuSE	ftp5.gwdg.de/pub/opensuse/repositories/home:/darix/openSUSE_10.3/i586/since-0.5-2.1.i586.rpm

since for AIX

since is a tail(1) work-alike that remembers how much of a file you have viewed and displays only what's new when you next view that file.

Downloaded from:	ftp://ftp.linux.ucla.edu/debian/pool/main/s/since/
Last update:	2002/01/30

AIX	Version	Binary	Source
4.1	0.3	[Download] (8.0 KB)	[Download] (25.5 KB)
4.2	0.3	[Download] (8.1 KB)	[Download] (25.5 KB)
4.3	0.3	[Download] (8.1 KB)	[Download] (25.7 KB)
5.1	0.3	[Download] (21.5 KB)	[Download] (40.3 KB)

Please note that some browsers download the files as uncompressed tar archives

Problems downloading? Please read the FAQ

Index of -ubuntu-pool-universe-s-since

• Parent Directory
• since_0.5-2.diff.gz
• since_0.5-2.dsc
• since_0.5-2_amd64.deb
• since_0.5-2_i386.deb
• since_0.5-2_powerpc.deb
• since_0.5-2_sparc.deb
• since_0.5-4.diff.gz
• since_0.5-4.dsc
• since_0.5-4_amd64.deb
• since_0.5-4_i386.deb
• since_0.5-5.diff.gz
• since_0.5-5.dsc
• since_0.5-5_amd64.deb
• since_0.5-5_i386.deb
• since_0.5.orig.tar.gz

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since - What is since

PPT tail

tail (Unix) - Wikipedia, the free encyclopedia

• CCZE is tail-like while displaying its output in color
• pctail Like CCZE: Python Colorized TAIL, a colorized tail made in python which tails and colorizes syslog output.
• root-tail displays the output in the X-server root window
• Inotail: the regular tail polls every second to see if new data can be displayed. Inotail uses the Linux kernel's inotify-interface so that it only checks for new data when there really is some.
• MultiTail not only displays logfiles in colors, it can also merge, filter, scrollback and split a terminal window in subwindows. It is more or less a combination of tail, sed, watch, CCZE/pctail, grep, diff, Beeper and others.

docs.sun.com man pages section 1 User Commands

TTTT head and tail

MultiTail

Most admins are already familiar with using tail -f logfile to watch system, application, and error logs when they're troubleshooting. However, the tail utility only follows one file at a time. If you need to watch two or more logfiles at the same time, which is fairly common, the MultiTail < http://www.vanheusden.com/multitail/ > utility by Folkert van Heusden is an excellent tool to have handy.

Basically, MultiTail handles two or more files simultaneously, and presents them in a split-screen view that makes it convenient to watch two, three, or more logfiles at the same time. This has come in particularly handy for me when troubleshooting issues with Web sites and mail issues. Technically, one can replicate the MultiTail experience by using GNU Screen to create a split screen environment and using |tail -f /logfile/ |multiple times -- but why? MultiTail makes it simple.

freshmeat.net Project details for inotail

inotail is a replacement for the 'tail' program found in the base installation of every Linux/Unix system. It makes use of the inotify infrastructure in recent versions of the Linux kernel to speed up tailing files in the follow mode (the '-f' option). Standard tail polls the file every second by default, while inotail listens to special events sent by the kernel through the inotify API to determine whether a file needs to be reread.

Etc

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