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Shell Programming and Scripting

How to loop this process?

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Top Forums Shell Programming and Scripting How to loop this process?
# 8  
Old 11-15-2010
I suppose seq loses points for fork/exec! In ksh, you have c-ish math in (()):
Code:
$ i=0;while (( ( i+= 1 ) < 6 ))
do
echo Processing $i
done
Processing 1
Processing 2
Processing 3
Processing 4
Processing 5
$

# 9  
Old 11-15-2010
Quote:
Originally Posted by DGPickett
I suppose seq loses points for fork/exec! In ksh, you have c-ish math in (()):
Code:
$ i=0;while (( ( i+= 1 ) < 6 ))
do
echo Processing $i
done
Processing 1
Processing 2
Processing 3
Processing 4
Processing 5
$

seq is alternative solution in this..like you say builtin (keyword) solutions are better and fast because of the access shell inertals is more easy to consider the fork() process Smilie
# 10  
Old 11-15-2010
Actually, execvp() takes about 10x more time than fork(), never mind vfork(), understandably as it has to search PATH and do loading and dynamic linking. Smilie
# 11  
Old 11-16-2010
Quote:
Originally Posted by DGPickett
Actually, execvp() takes about 10x more time than fork(), never mind vfork(), understandably as it has to search PATH and do loading and dynamic linking. Smilie
Smilie but if we think work in current shell (not in a script) which logged in then i think have no use for load the dynamic links (already loaded with current shell)
# 12  
Old 11-16-2010
Dynamic linking is done afresh with every exec*(). even though the pages are almost certainly in RAM, still, it takes substantially more time. This is good to remember in case you ever get the idea that dividing code into two smaller processes will save time.
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