Commands by raiden (1)

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Rebuild a Delimited File with a Unique Delimiter
Useful for CSV files. In the command, the file in question is comma delimited but contains double quoted fields containing commas and contains no @ symbols (as confirmed with http://www.commandlinefu.com/commands/view/9998/delimiter-hunting). This command converts the delimiting commas to @s while preserving the commas in the fields using the "uniqueString" to mark the ends of lines.

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.

Generate a (compressed) pdf from images
use imagemagik convert

Speak the top 6 lines of your twitter timeline every 5 minutes.....
Pump up the chatter, run this script on a regular basis to listen to your twitter timeline. This is a rough first cut using several cli clips I have spotted around. There is no facility to not read those things already read to you. This could also easily be put in a loop for timed onslaught from the chatterverse, though I think it might violate several pointsof the Geneva Convention UPDATE - added a loop, only reads the first 6 twits, and does this every 5 mins.

Convert a single-page PDF to a hi-res PNG, at 300dpi
If you skip this part: $ -density 300x300 you'll get a very lo-res image.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Create incremental backups of individual folders using find and tar-gzip
Problem: I wanted to backup user data individually, using and incremental method. In this example, all user data is located in "/mnt/storage/profiles", and about 25 folders inside, each with a username ( /mnt/storage/profiles/mike; /mnt/storage/profiles/lucy ...) I need each individual folder backed up, not the whole "/mnt/storage/profiles". So, using find while excluding directories depth and creating two variables (tarfile=username & desdir=destination), tar will create a .tgz file for each folder, resulting in a "mike_2013-12-05.tgz" and "lucy_2013-12-05.tgz".

Run a command if today is the last day of the month
This is handy to just shove into a daily cron entry. If you do use cron, make sure to escape the %d with \%d or it will fail.

Listen Digitally Imported Radio from CLI (without premium!)
This commands does just two things: fakes user agent (the one was taken from recent Android app) and sends the (possibly) listener ID (it can be any - I put "1" here because it works like a charm - after the name of stream ?1 as you can see). Look for the list of stations here: http://pub7.di.fm Or here: https://goo.gl/pdhhpQ Best regards, sxiii :)

tail, with specific pattern colored


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