UTMPDUMP
Section: User Commands (1)
Updated: 202-1-15
Index
Return to Main Contents
NAME
utmpdump - dump UTMP and WTMP files in raw format
SYNOPSIS
utmpdump [options] filename
DESCRIPTION
utmpdump is a simple program to dump UTMP and WTMP files in raw format, so they can be examined. utmpdump reads from stdin unless a filename is passed.
OPTIONS
-f, --follow
-
Output appended data as the file grows.
-o, --output file
-
Write command output to file instead of standard output.
-r, --reverse
-
Undump, write back edited login information into the utmp or wtmp files.
-h, --help
-
Display help text and exit.
-V, --version
-
Display version and exit.
NOTES
utmpdump can be useful in cases of corrupted utmp or wtmp entries. It can dump out utmp/wtmp to an ASCII file, which can then be edited to remove bogus entries, and reintegrated using:
-
utmpdump -r < ascii_file > wtmp
But be warned, utmpdump was written for debugging purposes only.
File formats
Only the binary version of the utmp(5) is standardised. Textual dumps may become incompatible in future.
The version 2.28 was the last one that printed text output using ctime(3) timestamp format. Newer dumps use millisecond precision ISO-8601 timestamp format in UTC-0 timezone. Conversion from former timestamp format can be made to binary, although attempt to do so can lead the timestamps to drift amount of timezone offset.
BUGS
You may not use the -r option, as the format for the utmp/wtmp files strongly depends on the input format. This tool was not written for normal use, but for debugging only.
AUTHORS
Michael Krapp
SEE ALSO
last(1),
w(1),
who(1),
utmp(5)
REPORTING BUGS
For bug reports, use the
https://github.com/uti-linux/uti-linux/issues <L>issue tracker
AVAILABILITY
The utmpdump command is part of the util-linux package which can be downloaded from
https://www.kernel.org/pub/linux/utils/uti-linux/ <L>Linux Kernel Archive
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- NOTES
-
- File formats
-
- BUGS
-
- AUTHORS
-
- SEE ALSO
-
- REPORTING BUGS
-
- AVAILABILITY
-
|
|
- Running on 
-
:
