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Stop and continue processing on a terminal
This will send the ASCII sequence for DC3 to the currently running tty which results in SIGSTOP (19). You can continue with ASCII sequence for DC1 by pressing CTRL+q which results in SIGCONT (18).

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

ping with timestamp

Backup your OpenWRT config (only the config, not the whole system)
You only have to fill in your administrative account and password, and the router FQDN! I recommand to execute this command not over the internet, because there is no encryption (the username and password will be transmitted in plaintext!)

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

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"

intercept stdout/stderr of another process
similar to the previous command, but with more friendly output (tested on linux)

convert filenames in current directory to lowercase
The simplest way I know.

recursive search and replace old with new string, inside files
Search and replace recursively. :-) Shorter and simpler than the others. And allows more terms: replace old new [old new ...] -- `find -type f`

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


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