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Top Forums Shell Programming and Scripting Help to get a second column value from a file Post 302316345 by cfajohnson on Thursday 14th of May 2009 08:59:14 PM
Old 05-14-2009
Quote:
Originally Posted by ghostdog74
just in case file is big,

If the file is large, you shouldn't be using a shell loop.
Quote:
putting IFS outside of while loop will be beneficial.

Putting IFS outside the loop has the disadvantage of changing it for commands inside the body of the loop as well as for the read command.
 

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COLRM(1)						    BSD General Commands Manual 						  COLRM(1)

NAME
colrm -- remove columns from a file SYNOPSIS
colrm [start [stop]] DESCRIPTION
The colrm utility removes selected columns from the lines of a file. A column is defined as a single character in a line. Input is read from the standard input. Output is written to the standard output. If only the start column is specified, columns numbered less than the start column will be written. If both start and stop columns are spec- ified, columns numbered less than the start column or greater than the stop column will be written. Column numbering starts with one, not zero. Tab characters increment the column count to the next multiple of eight. Backspace characters decrement the column count by one. ENVIRONMENT
The LANG, LC_ALL and LC_CTYPE environment variables affect the execution of colrm as described in environ(7). EXIT STATUS
The colrm utility exits 0 on success, and >0 if an error occurs. SEE ALSO
awk(1), column(1), cut(1), paste(1) HISTORY
The colrm command appeared in 3.0BSD. BSD
August 4, 2004 BSD
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