Search This Blog

Monday, December 29, 2008

How to create pictures thums in the one line

The following command can be paste as a one line
for i in `find /path/to/directory/with/pictures  -iname "*.JPG"`;\
convert $i -resize 800x600 `dirname $i`/thumb-`basename $i`;\
The find command return a whole path to a file. But we want to add thumb- before the actual name of a file. Therefore `dirname $i` ensure that convert get the proper path and `basename $i` the actual file name (preceded by thumb-). It is also worth to note the iname option of find command. It is case insensitive version of the name.

Monday, December 22, 2008

Another Awk one-liner

This one-liner printing third word from the lines beginning with "Mem:" (precisely the lines which first word is "Mem:") but adding the serial number before the word.
awk 'BEGIN {a=1} \
{if ( $1 == "Mem:" ) \
  {printf "%4d  %s\n",  a, $3; a++}}' \
free-prefork.log >mem-prefork.log
BTW. This script is to help me to plot a gnuplot graph based on "used memory" number from free command. plot "mem-prefork.log" will do the rest of job. UPDATE Mike Hommey post force me to rethink my scripts and I found easy way to eliminate if clause:
awk 'BEGIN {a=1} \
/^Mem:/  {printf "%4d  %s\n",  a, $3; a++}' \
free-prefork.log >mem-prefork.log

Monday, December 08, 2008

Gnuplot with readline on MacOSX

Recently, I tried to use gnuplot on a Mac, and, of course, it wasn't working properly. Apple prepared and shipped with MacOS its own (broken) version of readline library with didn't work with gnuplot (known bug). So I grabbed the sources of readline, applied all of patches and built mine version of readline. Next, I added the proper option to gnuplot configure file, but it wasn't pass to makefile. I looked into the Makefiles and found the the TERMLIBS option had to be change. I.e. using such command:
find . -name Makefile \
-exec sed -i.old "s/TERMLIBS\ =/TERMLIBS = -L\/usr\/local\/lib/" {} \; 
Two more things about gnuplot and MacOSX.
  1. I started to think to make a for MacOSX, but sure how it should work.
  2. I found that X11 term is much better then Aqua, in particular, it's allow to rotate 3D (s)plots.

Tuesday, December 02, 2008

Header for bonnie++ csv file

Recently I started to use bonnie++ to perform some disk tests. One of the thing annoy me is that bonnie++ output has no the 'csv header' describing what is in which column. It makes overview of results in a spreadsheet rather hard. Therefore I created my own one.
,,Per Chr, ,Block, ,Rewrite, ,Per Chr, ,Block, ,Seeks, ,Create, ,Read, ,Delete, ,Create, ,Read, ,Delete
You can save above lines in the file called i.e. bonnie-header.csv and then cat it before csv part of bonnie.out file (of course it can have different name), by:
cat bonnie-header.csv `tail -1 bonnie.out` >bonnie.csv
After that the output should looks similar to this one: BTW. I found that default number of files creating for metadata benchmarks is low, so I increased it to 128.