Help required to understand a variable in shell script!!!


 
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# 1  
Old 03-19-2009
Java Help required to understand a variable in shell script!!!

Hi,

I need to understand the following script:

a=`dirname $0`
b=`uname -s`
if [ "${a:0:1}" = "/" ] ; then
c=$a/../../../platforms/$b/extlib
else
c=`pwd`/$a/../../../platforms/$b/extlib
fi

There are a bunch of variable assignments going on here!!!
What does this variable means: "${a:0:1}"

Thanks!!!
# 2  
Old 03-19-2009
Writing in a large font does not imply urgency nor will it generate responses any sooner.
As for your question, ${a:0:1} means "Take the value of variable a and return the substring starting at position 0 with a length of 1". It's a simple test to see if it's an absolute or relative path.
# 3  
Old 03-19-2009
Bug

Ohhh...........SORRY!!!

I did'nt meant for any sort if urgency or to get immediate repsonse!!!

I only did it since it will be properly legilble otherwise when I typed I myself was not able to decipher it.
That was my only sole intention.

Any ways SORRY for that..and I will keep in mind from the next time.

Thanks for the reply and info!!!
 
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