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 ALSO¶
shtool(1), BSD
newsyslog(8).