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Install pip with Proxy
Installs pip packages defining a proxy

Default value or argument
I used it for this function, which prints hashes: function liner { num_lines=${1:-42} echo printf %${num_lines}s|tr " " "#" echo } Note the colon-dash, instead of the usual colon-equals.

check open ports without netstat or lsof

Connect to SMTP server using STARTTLS
Allows you to connect to an SMTP server over TLS, which is useful for debugging SMTP sessions. (Much like telnet to 25/tcp). Once connected you can manually issue SMTP commands in the clear (e.g. EHLO)

Detect Language of a string
Usage: $ detectlanguage Example: $ detectlanguage hola

Connect to TCP port 5000, transfer data and close connexion.
With no '-q 0' switch, nc simply waits, and whatever awaits the data hangs.

Lists all listening ports together with the PID of the associated process
The PID will only be printed if you're holding a root equivalent ID.

Rename files in batch

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" }

search for a file in PATH
Also searches for aliases and shell builtins


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