Commands by Yim (1)

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Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

start a VNC server for another user

keep an eye on system load changes
helps you keep watch on the load of a system, without having to stare constantly at the terminal. The -d argument to watch highlights the difference from the last run, making it easier to note how the load is fluctuating. The sed command just strips off the information about how long the box has been up, and how many users are logged in.

Get length of current playlist in xmms2

Override and update your locally modified files through cvs..

Test for Weak SSL Ciphers
...if you get a certificate back, the server is accepting weak SSL ciphers

Update IP filter for qBittorrent
Downloads Bluetack's level 1 IP blocklist in .p2p format, suitable for various Bittorrent clients.

Using netcat to copy files between servers
It bypasses encryption overhead of SSH and depending on configuration can be significantly faster. It's recommended to use only in trusted networks.

Extract domain from URl
Extracts 2nd-level domain part (or 3rd level, for co.* or com.*) from the URI's hostname. See sample output.

concatenate compressed and uncompressed logs
with zcat force option it's even simpler.


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