SHTOOL-ROTATE.TMP(1) GNU Portable Shell Tool SHTOOL-ROTATE.TMP(1)NAME
shtool rotate - GNU shtool log file rotation
SYNOPSIS
shtool rotate [-v|--verbose] [-t|--trace] [-f|--force] [-n|--num-files
count] [-s|--size size] [-c|--copy] [-r|--remove] [-a|--archive-dir
dir] [-z|--compress [tool:]level] [-b|--background] [-d|--delay]
[-p|--pad len] [-m|--mode mode] [-o|--owner owner] [-g|--group group]
[-M|--migrate cmd] [-P|--prolog cmd] [-E|--epilog cmd] file [file ...]
DESCRIPTION
This command rotates a logfile file by subsequently creating up to
count (optionally compressed) archive files of it. Archive files are
named "file.number[compress-suffix]" where number is the version
number, 0 being the newest and "count-1" the oldest.
A rotation step consists of the following steps
1. remove last archive file 2. shift archive file numbers 3. create
archive file 0 from file 4. truncate/recreate file
OPTIONS
The following command line options are available.
-v, --verbose
Display some processing information.
-t, --trace
Enable the output of the essential shell commands which are
executed.
-f, --force
Force silent creation of archive directory if it does not exists.
Also skip missing intermediate logfiles in the rotation step.
Default is to exit with error in both cases. FIXME
-n, --num-files count
Create count archive files. Default is 10.
-s, --size size
Only rotate if logfile exceeds size. The argument size can be
specified also with the trailing units "K" (kilo), "M" (mega) or
"G" (giga). The "prolog" and "epilog" are only executed if rotation
actually takes place.
-c, --copy
Copy file to archive then truncate original. The default is to move
file to archive.
Unless an application reopens its logfile it will continue to write
to the same file. In the default move case the application will
write to the archive which it had previously opened as file. In the
copy case the application will write to the original file. The
drawback of the copy approach is that logfile entries are lost when
they are written to file between the execution of the copy and the
truncation operation. The drawback of the move approach is that the
application needs to detect the move or must be triggered to reopen
its log (i.e. through epilog).
-r, --remove
Removes file after rotation instead of providing a new empty file.
-a, --archive-dir dir
Specify the archive directory. Default is to create archives in the
same directory as file is located.
-z, --compress [tool:]level
Enables compression of archive files with compression level level
By default, the tools bzip2(1), gzip(1) and compress(1) are
searched for in $PATH, but one also can override this by prefixing
the compression level with one of the three particular tool names.
-b, --background
Enable background compression.
-d, --delay
Delays the compression of archive file number 0. This is useful if
``-c'' is not used, because an application might continue to write
to archive file 0 through an already open file handle.
-p, --pad len
Enables padding with leading zeros in the number part of the
filename "file.numbercompress-suffix". The default padding len is
1. This is interesting if more than 10 archive files are used,
because it leads to still sorted directory listings.
-m, --mode mode
The file mode applied to the created files, see chmod(1). Setting
mode to "-" skips this step and leaves the operating system default
which is usually based on umask(1). Some file modes require
superuser privileges to be set. Default is 0755.
-o, --owner owner
The file owner name or id applied to the created files, see
chown(1). This option requires superuser privileges to execute.
Default is to skip this step and leave the operating system default
which is usually based on the executing uid or the parent setuid
directory.
-g, --group group
The file group name or id applied to the created files, see
chgrp(1). This option requires superuser privileges to execute to
the fullest extend, otherwise the choice of group is limited on
most operating systems. Default is to skip this step and leave the
operating system default which is usually based on the executing
gid or the parent setgid directory.
-M, --migrate cmd
Execute a "migration" command just before the archive file number
count-1 is removed from the filesystem. The specified cmd receives
the archive filename as command line argument.
-P, --prolog cmd
Execute a "prolog" command before the rotation step. Useful in
conjunction with -s.
-E, --epilog cmd
Execute a "epilog" command after the rotation step. Useful in
conjunction with -s.
EXAMPLE
# shell script
shtool rotate -n10 -s1M -zbzip2:9 -d -r /var/log/ap.access.log
shtool rotate -n5 -s128K -zbzip2:9 -d -r /var/log/ap.error.log
apachectl graceful
HISTORY
The GNU shtool rotate command was originally written by Ralf S.
Engelschall <rse@engelschall.com> in 2001 for GNU shtool. Its
development was prompted by the need to have a flexible logfile
rotation facility in the OpenPKG project.
SEE ALSOshtool(1), BSD newsyslog(8).
18-Jul-2008 shtool 2.0.8 SHTOOL-ROTATE.TMP(1)
