Commands by mathias (5)

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Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

When was your OS installed?

ls only directories
Like normal ls, but only lists directories. Can be used with -l to get more details (ls -lad */)

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

A one-line web server in Ruby
Here's how to serve a directory in one line of Ruby. Handy for sharing files at a conference, for example.

Show number of NIC's, ports per nic and PCI address

Convert all WMF images to SVG recursively ignoring file extension case
This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.

bash/ksh function: given a file, cd to the directory it lives
fcd : file change directory A bash function that takes a fully qualified file path and cd's into the directory where it lives. Useful on the commadline when you have a file name in a variable and you'd like to cd to the directory to RCS check it in or look at other files associated with it. Will run on any ksh, bash, likely sh, maybe zsh.

Resample a WAV file with sox
Change the sample rate with sox, the swiss army knife of sound processing.

Get a diff of two json arrays
jq is amazing for manipulating json on the commandline, but the developers have some weird ideas about how to handle shell redirections. This command works around them. Further reading: https://github.com/stedolan/jq/issues/1110


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