Commands tagged motherboard (2)

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Change the From: address on the fly for email sent from the command-line
It's very common to have cron jobs that send emails as their output, but the From: address is whatever account the cron job is running under, which is often not the address you want replies to go to. Here's a way to change the From: address right on the command line. What's happening here is that the "--" separates the options to the mail client from options for the sendmail backend. So the -f and -F get passed through to sendmail and interpreted there. This works on even on a system where postfix is the active mailer - looks like postfix supports the same options. I think it's possible to customize the From: address using mutt as a command line mailer also, but most servers don't have mutt preinstalled.

Validate all XML files in the current directory and below
If everything validates, there's no output. Can be handy to run on a cron job set up to email output.

Multi line grep using sed and specifying open/close tags
Working with log files that contains variable length messages wrapped between open and close tags it may be useful to filter the messages upon a keyword. This works fine with GNU sed version 4.2 or higher, so pay attention to some unix distros (solaris, hp-ux, etc.). Linux should be ok.

Generate binary sequence data

du disk top 10
fancy command line ncdu clone

Counts number of lines (in source code excluding comments)
I took java to make the find command simpler and to state that it works for any language supported by cpp. cpp is the C/C++ preprocessor (interprets macros, removes comments, inserts includes, resolves trigraphs). The -fpreprocessor option tells cpp to assume the input has already been preprocessed so it will only replace comment lines with blank lines. The -L 1 option tells xargs to launch one process for each line, indeed cpp can only process one file at the time...

Indent all the files in a project using emacs
use -iname \*[.ch] instead of -iname \*.c -o -iname \*.h

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Get your commandlinefu points (upvotes - downvotes)
This will calculate the your commandlinefu votes (upvotes - downvotes). Hopefully this will boost my commandlinefu points.

automatically ditch old versions in a conflict
This is not exactly a commandline, but a vim macro to automatically ditch the "old" version of a conflict when dealing with the naster

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