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Add temporary swap space
In addition to a swap partition, Linux can also use a swap file. Some programs, like g++, can use huge amounts of virtual memory, requiring the temporary creation of extra space.

Show which programs are listening on TCP ports
Alternative: $ ss -tlpn

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

Colorful man
Colourful with vim regex finding goodness! Replace the 'man' with the page to be looked up. I actually have as a function in my .profile function vman { /usr/bin/man $* | /usr/bin/col -b | /usr/bin/iconv -c | view -c 'set ft=man nomod nolist nospell nonu' -

user 'tr' to convert mixed case in a file to lower case
convert mixed case in a file to lower case

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" }

Bind a key with a command
the -x option is for binding to a shell command

Decode base64-encoded file in one line of Perl
Another option is openssl.

Video thumbnail
Faster thumbnail creation than '-itsoffset' $ffmpeg -itsoffset -4 -i test.avi -vcodec mjpeg -vframes 1 -an -f rawvideo -s 320x240 test.jpg


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