Commands by jbsnyder (0)

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Increase mplayer maximum volume
use '0' and '9' to increase/decrease volume. this is useful on laptops with low speaker volume.

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" }

shutdown pc in a 4 hours
you may as well use shutdown -h 18:32 to shutdown your machine at 18:32.

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Compression formats Benchmark
See: http://imgur.com/JgjK2.png for example. Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1). Run: $ gnuplot -persist

generate random password
for Mac OS X

Merge several pdf files into a single file

Generate a shortened URL with is.gd
Check the API. You shouldn't need sed. The print-newline at the end is to prevent zsh from inserting a % after the end-of-output. Also works with http://v.gd

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

use wget to check if a remote file exists

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