utmpdump(1) - phpMan
UTMPDUMP(1) System Administration UTMPDUMP(1)
utmpdump - dump UTMP and WTMP files in raw format
utmpdump [options] [filename]
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.
Output appended data as the file grows.
-o, --output file
Write command output to file instead of standard output.
Undump, write back edited login information into the utmp or wtmp files.
Display help text and exit.
Display version information and exit.
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 reinte‐
utmpdump -r < ascii_file > wtmp
But be warned, utmpdump was written for debugging purposes only.
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.
last(1), w(1), who(1), utmp(5)
The utmpdump command is part of the util-linux package and is available from Linux Kernel
util-linux July 2012 UTMPDUMP(1)