Commands by Timothy (2)

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repeat any string or char n times without spaces between
(here is character '+' repeated 80 times) Sometimes needed to enhance the title of the script.

The BOFH Excuse Server

Convert tab separate file (TSV) to JSON with jq
With this command you can convert a tab separate file (TSV) into a JSON file with jq. For example, this input.tsv i-0b9adca882e5e6326 172.16.0.188 i-088dd69e5c3624888 172.16.0.102 i-0e70eac180537d4aa 172.16.0.85 will produce the showed output.

list files recursively by size

Determine if photos have been rotated to portrait orientation instead of normal landscape orientation
Most people take photos in landscape orientation (wider than it is tall). Sometimes though you turn the camera sideways to capture a narrow/tall subject. Assuming you then manually rotate those picture files 90 degrees for proper viewing on screen or photo frame, you now have a mix of orientations in your photos directory. This command will print out the names of all the photos in the current directory whose vertical resolution is larger than its horizontal resolution (i.e. portrait orientation). You can then take that list of files and deal with them however you need to, like re-rotating back to landscape for consistent printing with all the others. This command requires the "identify" command from the ImageMagick command-line image manipulation suite. Sample output from identify: $ identify PICT2821.JPG PICT2821.JPG JPEG 1536x2048 1536x2048+0+0 8-bit DirectClass 688KB 0.016u 0:00.006

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

check open ports without netstat or lsof

See a full list of compiler defined symbols
From http://lists.debian.org/debian-devel/2001/01/msg00971.html .

Quickly create simple text file from command line w/o using vi/emacs
1. Issue command 2. After angled bracket appears, enter file contents 3. When done, type "EOF"

Currency Conversion
eg: currency_convert 1 usd inr


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