Commands tagged tail -f (13)

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Join lines
It's works only when you replace '\n' to ONE character.

If (and only if) the variable is not set, prompt users and give them a default option already filled in.
The read command reads input and puts it into a variable. With -i you set an initial value. In this case I used a known environment variable.

Set RGB gamma of secondary monitor
This command first determines whether a second screen is connected. If this is the case, it sets the screen's RGB gamma via xrandr. Useful for cheap or slightly defective monitors with a tint. In this example a yellowing/champagne color deviation is compensated for by decreasing the red and the green portion of the image.

Continuously show wifi signal strength on a mac
The closer to zero the better.Credit to TheSeb on macrumors: http://forums.macrumors.com/showthread.php?t=1289884

Search some text from all files inside a directory

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

Use /dev/full to test language I/O-failsafety
The Linux /dev/full file simulates a "disk full" condition, and can be used to verify how a program handles this situation. In particular, several programming language implementations do not print error diagnostics (nor exit with error status) when I/O errors like this occur, unless the programmer has taken additional steps. That is, simple code in these languages does not fail safely. In addition to Perl, C, C++, Tcl, and Lua (for some functions) also appear not to fail safely.

Short and sweet output from dig(1)
Turn off almost all of dig's output except for what you'd see in a zone file. This can also be put into ~/.digrc.

Show the command line for a PID, converting nulls to spaces and a newline
If you cat the file, all the parts of the command line are bunched up. If you use tr to convert the nulls to spaces, you're still left without a newline unless you add another step. This command does everything for you.

List the size (in human readable form) of all sub folders from the current location
Simple and easy to remember. -h is human, -d1 = depth 1. disk usage, human, depth 1


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