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Full Discussion: Functions in a shell script
Top Forums Shell Programming and Scripting Functions in a shell script Post 302902757 by rbatte1 on Thursday 22nd of May 2014 06:15:37 AM
Old 05-22-2014
What sort of processing are you doing? If there are lots of files being read & re-read, that will cost time. If there are lots of calls to external programs (grep, cut, tr, sed, awk etc.) in loops, then that will cost time.

For example are you reading a 10,000 line input file and for each line you use grep to scan another large file or set of files for each one, then there may be a better way to re-work the logic of avoid repetitive calls.

Can you give us a logical description of what it does? Roughly how many lines does your function have? (excluding comments and blanks if you can)

Can you put some tracing in to see where it is spending most of it's time?



Robin
 

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GREP(1) 						      General Commands Manual							   GREP(1)

NAME
grep - search a file for a pattern SYNOPSIS
grep [ option ... ] pattern [ file ... ] DESCRIPTION
Grep searches the input files (standard input default) for lines (with newlines excluded) that match the pattern, a regular expression as defined in regexp(6). Normally, each line matching the pattern is `selected', and each selected line is copied to the standard output. The options are -c Print only a count of matching lines. -h Do not print file name tags (headers) with output lines. -i Ignore alphabetic case distinctions. The implementation folds into lower case all letters in the pattern and input before interpre- tation. Matched lines are printed in their original form. -l (ell) Print the names of files with selected lines; don't print the lines. -L Print the names of files with no selected lines; the converse of -l. -n Mark each printed line with its line number counted in its file. -s Produce no output, but return status. -v Reverse: print lines that do not match the pattern. Output lines are tagged by file name when there is more than one input file. (To force this tagging, include /dev/null as a file name argument.) Care should be taken when using the shell metacharacters $*[^|()= and newline in pattern; it is safest to enclose the entire expression in single quotes '...'. SOURCE
/sys/src/cmd/grep.c SEE ALSO
ed(1), awk(1), sed(1), sam(1), regexp(6) DIAGNOSTICS
Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs. GREP(1)
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