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Skip banner on ssh login prompt
This allows you to skip the banner (usually /etc/issue.net) on ssh connections. Useful to avoid banners outputted to your mail by rsync cronjobs.

Get the absolute path of a file

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

List open files that have no links to them on the filesystem
I have come across a situation in the past where someone has unlinked a file by running an 'rm' command against it while it was still being written to by a running process. The problem manifested itself when a 'df' command showed a filesystem at 100%, but this did not match the total value of a 'du -sk *'. When this happens, the process continues to write to the file but you can no longer see the file on the filesystem. Stopping and starting the process will, more often than not, get rid of the unlinked file, however this is not always possible on a live server. When you are in this situation you can use the 'lsof' command above to get the PID of the process that owns the file (in the sample output this is 23521). Run the following command to see a sym-link to the file (marked as deleted): $ cd /proc/23521/fd && ls -l Truncate the sym-link to regain your disk space: $ > /proc/23521/fd/3 I should point out that this is pretty brutal and *could* potentially destabilise your system depending on what process the file belongs to that you are truncating.

Graphical tree of sub-directories with files
The command finds every item within the directory and edits the output so that subdirectories are and files are output much like the tree command

Rename files in batch

get the latest version
to download latest version of "util", maybe insert a sort if they wont be shown in right order. curl lists all files on mirror, grep your util, tail -1 will gets the one lists on the bottom and get it with wget

locate bin, src, and man file for a command

View a colorful logfile using less

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.


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