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Put split files back together, without a for loop
After splitting a file, put them all back together a lot faster then doing $cat file1 file2 file3 file4 file5 > mainfile or $for i in {0..5}; do cat file$i > mainfile; done When splitting, be sure to do split -d for getting numbers instead of letters

Join lines
It's works only when you replace '\n' to ONE character.

Search for in which package the specified file is included.

Replace spaces in filenames with underscores
It's the rename-tool from debians perl-package.

Record camera's output to a avi file
video.avi is the resulting file. Press Ctrl+c to stop the recording. You can change the OVC option to another to record into a different format.

Show directories in the PATH, one per line
Shorter version.

Securely stream (and save) a file from a remote server
Securely stream a file from a remote server (and save it locally). Useful if you're impatient and want to watch a movie immediately and download it at the same time without using extra bandwidth. This is an extension of snipertyler's idea. Note: This command uses an encrypted connection, unlike the original.

Wait for file to stop changing
Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.

Compare a remote dir with a local dir
You can compare directories on two different remote hosts as well: $ diff -y

Convert CSV to JSON - Python3 and Bash function
Based / Inspired by malathion's below command http://www.commandlinefu.com/commands/view/20528/convert-csv-to-json Is written for python3 and is very easy to use csv2json *csv will convert all files ending in csv to json eg csv2json file.csv will output a file to file.json Validity of json tested in python3 and below site https://jsonformatter.curiousconcept.com/


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