Commands by mack (10)

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Is it a terminal?
Oddly, the isatty(3) glibc C call doesn't have a direct analogue as a command 'isatty(1)'. All is not lost as you can use test(1). For example, your script might be run from a tty or from a GUI menu item but it needs to get user-input or give feedback. Now your script can test STDIN with 'isatty 0' or STDOUT with 'isatty 1' and use xmessage(1) if the tty is not available. The other way to test for this is with 'tty -s' - but that's only for STDIN.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Base conversions with bc
Easily convert numbers to their representations in different bases. Passing "ibase=16; obase=8; F2A" to bc will convert F2A (3882 in decimal) from Hex to Octal, and so on.

Awesomeness Confirmation Bias

recursive search and replace old with new string, inside files
This command find all files in the current dir and subdirs, and replace all occurances of "oldstring" in every file with "newstring".

list block devices
Shows all block devices in a tree with descruptions of what they are.

list files recursively by size

The program listening on port 8080 through IPv6

Protect directory from an overzealous rm -rf *
Forces the -i flag on the rm command when using a wildcard delete.

Find public IP when behind a random router (also see description)
Depends on GET. You can also replace GET with curl, or `wget -qO -` if GET isn't available.


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