Commands tagged expr (3)

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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"

Find the package that installed a command

Show directories in the PATH, one per line
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

list files recursively by size

Live stream a remote desktop over ssh using only ffmpeg
Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.

Update twitter via curl (and also set the "from" bit)
An improvement of the original (at: http://www.commandlinefu.com/commands/view/2872/update-twitter-via-curl) in the sense that you see a "from cURL" under your status message instead of just a "from API" ;-) Twitter automatically links it to the cURL home page.

Search for a string inside all files in the current directory
options: -n line nbrs, -i ignore case, -s no "doesn't exist", -I ignore binary args: * for all files of current dir (not hidden), .[!.]* for all hidden files I don't include by default the -R (recursive) option, which is not always useful. You add it by hand when needed.

Split lossless audio (ape, flac, wav, wv) by cue file
Do you have an entire album in a unique file and want to split it in individual tracks? If you also have the cue file you can do it! Packages for Debian-based systems users: * cuetools shntool * FLAC (.flac): flac * WavPack (.wv): wavpack * Monkey's Audio (.ape): libmac2 monkeys-audio (deb http://www.debian-multimedia.org sid main) NOTE: "sid" packages are unstable, but I didn't have problems with them. If you prefer, use the "stable" version repository. To transfer the tags, you can use this (works with .flac, .ogg and .mp3): $ cuetag sample.cue split-track*.flac

Capitalize the first letter of every word


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