Howto iterate through an input stream without a subshell or a read.

It sometimes comes up that the usual trick of reading in a stream with a pipe and a while loop doesn't work, since the pipe causes a subshell and any variables set in the subshell are unavailable to the parent.
For example the normal trick (output the first few lines of the /etc/services file, just the first two columns and not empty or comment lines):

[uphill@zagreb]: grep -v ^# /etc/services | grep -v ^$ | head | awk '{print $1" "$2;}'
tcpmux 1/tcp
tcpmux 1/udp
rje 5/tcp
rje 5/udp
echo 7/tcp
echo 7/udp
discard 9/tcp
discard 9/udp
systat 11/tcp
systat 11/udp
[u
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Howto use arrays in bash to store indexed information

Sometimes it's easier to write a quick script in bash that uses arrays rather than figure out how to do it with something more appropriate like awk or perl.

It's really very quick and simple. To start, declare your variable as an array

[uphill@host]: declare -a myvar

If the array is going to be global then add x to export it.

 

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.Xdefaults app-defaults not applying automatically

In RHEL4 and possibly other distros. The .Xdefaults file is not used, the file is now called .Xresources In /etc/X11/xinit/xinitrc-common, xrdb is passed .Xresources _after_ /etc/X11/Xresources. You can make systemwide changes in /etc/X11/Xresources, but they will be overridden by changes to .Xresources.
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Mind Path Technologies Pocket Point RF Remote in Acroread/Others (on Linux)

I'm hoping that someone else has a better solution for this one. We have a pocketpoint remote that works quite well for Power point presentations, but for Acrobat Reader the keybinding is not good. The remote sends p for prior/previous and n for next, which is understood by powerpoint and not by Adobe. I wrote the following lame script to fix this. It works for the most part, but you lose the p and n keys during the presentation. [includecode#../scripts/pocketpoint]
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