Commands by tzot (1)

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Get IP from hostname
Get the IP of a hostname.

no # comments, blank lines, white space. # can start in any column
The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: $ noc /etc/hosts or $ grep server /etc/hosts | noc Change to nawk depending awk versions.

A child process which survives the parent's death (for sure)
Test scenario: * Open xterm (or konsole, ...) * Start xeyes with: ( xeyes & ) * Close the xterminal The xeyes process should be still running.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Show all configured ipv4
Short list of all ip. Shows even the newly supported multiple ip address on the same interface (see eth1). For ipv6 use -6

Check how far along (in %) your program is in a file
Imagine you've started a long-running process that involves piping data, but you forgot to add the progress-bar option to a command. e.g. $ xz -dc bigdata.xz | complicated-processing-program > summary . This command uses lsof to see how much data xz has read from the file. $ lsof -o0 -o -Fo FILENAME Display offsets (-o), in decimal (-o0), in parseable form (-Fo) This will output something like: . p12607 f3 o0t45187072 . Process id (p), File Descriptor (f), Offset (o) . We stat the file to get its size $ stat -c %s FILENAME . Then we plug the values into awk. Split the line at the letter t: -Ft Define a variable for the file's size: -s=$(stat...) Only work on the offset line: /^o/ . Note this command was tested using the Linux version of lsof. Because it uses lsof's batch option (-F) it may be portable. . Thanks to @unhammer for the brilliant idea.

Random Number Between 1 And X
If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.

Backup all databases in a MySQL container

list block devices
Shows all block devices in a tree with descruptions of what they are.


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