Commands by Bonster (27)

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Generate random password on Mac OS X
Feel free to put this in your ~/.profile: $ random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; } Then use it to generate passwords: $ random [:alnum:] 16 Or DNA sequences: $ random ACGT 256

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"

Find recursively, from current directory down, files and directories whose names contain single or multiple whitespaces and replace each such occurrence with a single underscore.
Note the g for global in the perl expression; without it, only the first occurrence in the name would be replaced.

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

show ALL iptable rules
show your current iptable rules from every available iptable table

Upgrade all perl modules via CPAN

give a binary the ability to open ports below 1024 as non root user
Binding a server to privileged port on Linux w/o running as root This is applicable to any service using privileged ports (< 1024), for instance to run a HTTP server on port 80 or a LDAP directory server on port 389 for example.

Delete all empty lines from a file with vim
If you need to delete lines that may contain space characters (such as tabs or spaces) as well as empty ones, try: $:v/\S/d Just an alternative.

Sets shell timeout
Useful in root's .profile - will auto-logout after TMOUT seconds of inactivity. Close after `seconds` inactive. export TMOUT=seconds (unefunge)

Check your unread Gmail from the command line
Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages. For some reason sed gets stuck on OS X, so here's a Perl version for the Mac: $ curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '' '{for (i=2; i


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