SINCE(1) User Manuals SINCE(1)NAMEsince - display content of a file since the last time
SYNOPSISsince [-aefhlmnqvxz] [-d seconds] [-s file] files
DESCRIPTIONsince is a utility designed to monitor log files. since is similar to
tail(2) as it also displays information appended to a file. However
since only displays the data which has been added since the last time
since was run. If since is run on a particular file for the first time,
then the entire file is displayed.
EXAMPLEsince /var/log/apache/{access,error}_log > /dev/null
lynx --dump http://localhost/ > /dev/null
since /var/log/apache/{access,error}_log
OPTIONS-a Make updates to the since state files atomic. This option con‐
figures since to use a temporary file and a rename(2) instead of
updating the state file in situ.
-d seconds
Specify the number of integer seconds to wait between polling
files for changes. This option is only relevant in conjunction
with the -f option and if the inotify mechanism is not being
used.
-e Print the header lines to standard error instead of standard
output.
-f Follow the specified files. This option is analogous to tail -f
as the files are also polled for changes until the process is
interrupted.
-h Print a terse help message.
-l Relaxed mode. If some data files are inaccessible since will not
fail completely.
-m Disable mmap(2), use read(2) instead to access state and data
files. Note that for certain smaller io operations read(2) may
be used even if this option has not been given.
-n Do not update the .since file which keeps track of file growth.
-q Make the utility operate more quietly.
-s filename
Specify the state file explicitly. Using this option will also
disable the use of fallback state files.
-v Increase the verbosity. This option can be given multiple times.
-x Ignore file arguments which have compressed extensions.
-z Discard output. Similar to redirecting the output to /dev/null,
but faster. If used in conjunction with the -f option, only the
initial output will be discarded.
FILES
.since
State file recording the length of the previously displayed
files. The location of the file can be set on the command line
using the -s option. If this option is not given, since will
check the SINCE environment variable for the location of the
state file. If the SINCE environment variable has not been set
since will use the HOME environment variable and store the
information in the file $HOME/.since. If the HOME variable is
not set, since will use a getpwuid(3) lookup. If all these fail
will use the file /tmp/since.
BUGSsince uses the inode of a file as its key, if that inode is recycled
since will get confused. since is not particularly efficient when
storing or looking up the stat(2) information. Functionality equivalent
to since can probably be achieved with a number of trivial shell
scripts.
COPYINGsince may only be used, distributed and modified in accordance with the
terms of the GPL (GNU General Public License) version 3 or newer as
published by the FSF (Free Software Foundation).
SEE ALSOtail(1), stat(2).
FreeBSD JULY 1998 SINCE(1)
