Commands using grep (1,935)

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'hpc' in the box - starts a maximum of n compute commands modulo n controlled in parallel
the block of the loop is useful whenever you have huge junks of similar jobs, e.g., convert high res images to thumbnails, and make usage out of all the SMP power on your compute box without flooding the system. note: c is used as counter and the random sleep $ r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r is just used as a dummy command.

Get MX records for a domain
command is shorter, output unnecessary longer

Save a file you edited in vim without the needed permissions (no echo)
Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

Extract audio from Mythtv recording to Rockbox iPod using ffmpeg
There are some pretty good live performances on late night TV. With Mythtv I record David Letterman, Jimmy Fallon, and Conan nightly all in HD from over the air broadcasts. If I find a live performance I like I copy it to my Rockboxed iPod using this command. The Rockbox firmware knows how to downmix 5.1 audio. The command above extracts the audio from the video starting at 58 minutes and 15 seconds. It ends at the end of the file since this was the last performance of the recording. The command creates an ac3 file. I copy the ac3 file to my Rockbox iPod and rock on.

Job Control
background and disown, but with a proper one-line syntax

find and reduce 8x parallel the size of JPG images without loosing quality via jpegoptim

list files recursively by size

Extract audio from a video
With the -vn switch we make our intentions clear and ask FFmpeg not to bother itself with the video. Next we specify the audio codec copy, which tells FFmpeg to use the same codec to encode the audio, which it uses to decode it. To keep things simple, we'll just keep the sampling and bitrate values the same.

Convert (almost) any video file into webm format for online html5 streaming
If you're using the experimental vorbis encoder (homebrew version of libffmpeg)

list files recursively by size


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