Commands by aysadk (92)

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Create a listing of all possible permissions and their octal representation.

Rename files in batch

Periodically run a command without hangups, and send the output to your e-mail
Run "ps -x" (process status) in the background every hour (in this example). The outputs of both "nohup" and "ps -x" are sent to the e-mail (instead of nohup.out and stdout and stderr). If you like it, replace "ps -x" by the command of your choice, replace 3600 (1 hour) by the period of your choice. You can run the command in the loop any time by killing the sleep process. For example $ ps -x 2925 ? S 0:00.00 sh -c unzip E.zip >/dev/null 2>&1 11288 ? O 0:00.00 unzip E.zip 25428 ? I 0:00.00 sleep 3600 14346 pts/42- I 0:00.01 bash -c while true; do ps -x | mail pascalv; sleep 3600; done 643 pts/66 Ss 0:00.03 -bash 14124 pts/66 O+ 0:00.00 ps -x $ kill 25428 You have mail in /mail/pascalv

Find out the starting directory of a script
Invoked from within a shell script, this will print the directory in which the script resides. Doesn't depend on external tools, /proc/self/*, etc.. (`echo` is a shell builtin.) To see the *current working* directory of a script, use `pwd`.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Show all LISTENing and open server connections, with port number and process name/pid

Insert a comment on command line for reminder
Comments can be used directly on the command line so I can save in the history a brief description of what command does.

Null a file with sudo

Octal ls
Do ls with permissions written in octal form.

Copy ssh keys to user@host to enable password-less ssh logins.
To generate the keys use the command ssh-keygen


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