Commands by tanj (1)

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small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

Verify MD5SUMS but only print failures
All valid files are withheld so only failures show up. No output, all checks good.

creating you're logging function for your script
You could also pipe to logger.

Reset terminal that has been buggered by binary input or similar

blktrace - generate traces of the i/o traffic on block devices
blktrace is a block layer IO tracing mechanism which provide detailed information about request queue operations up to user space. blkparse will combine streams of events for various devices on various CPUs, and produce a formatted output the the event information. It take the output of above tool blktrace and convert those information into fency readable form.

list all file extensions in a directory
... plus do a sort according frequency

Monitor dynamic changes in the dmesg log.
Other logs can be monitored similarly, e.g. $ watch "tail -15 /var/log/daemon.log"

change exif data in all jpeg's
this takes every jpg in the current directory and changes the exif data for manufactur and model. in my case i change it to LOMO LC-A because my scanner puts his data in there :]

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"

seq (argc=2) for FreeBSD


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