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Top Forums Shell Programming and Scripting Imitate head and tail command script Post 302364780 by Scott on Friday 23rd of October 2009 09:10:36 PM
Old 10-23-2009
Sounds like a homework thing?

Anyway.

Interactive = read
Cat
wc for finding out how many lines there are
A handful of other commands
Awk for everything else

Code:
FILE=$1

echo "How many lines?: "
read HowMany

echo "Heads or tails? "
read HoT
case "$HoT" in
  h) awk 'NR <= '$HowMany $FILE ;;
  t) awk 'NR > '$(($(wc -l < $FILE) - $HowMany)) $FILE
esac

(there's a distinct lack of error checking here! $1 is the filename when calling this as a script from the command line)

Last edited by Scott; 10-23-2009 at 10:16 PM.. Reason: wc < file => wc < $FILE
 

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CosPropertyService_PropertyNamesIterator(3erl)		     Erlang Module Definition		    CosPropertyService_PropertyNamesIterator(3erl)

NAME
CosPropertyService_PropertyNamesIterator - This module implements the OMG CosPropertyService::PropertyNamesIterator interface. DESCRIPTION
To get access to the record definitions for the structures use: -include_lib("cosProperty/include/CosPropertyService.hrl"). EXPORTS
reset(Iterator) -> ok Types Iterator = #objref This operation resets the position to the first property name. next_one(Iterator) -> Reply Types Iterator = #objref Reply = {boolean(), Name} Name = string() This operation returns true if a Property Name exists at the current position and the out parameter is a valid Property Name. If false is returned the out parameter is a non-valid Property Name. next_n(Iterator, HowMany) -> Reply Types Iterator = #objref HowMany = long() Reply = {boolean(), [Name]} Name = string() This operation returns true if the requested number of Property Names can be delivered and there are additional property names. If false is returned a sequence of max HowMany property names will be returned and no more Property Names can be delivered. destroy(Iterator) -> ok Types Iterator = #objref This operation will terminate the Iterator and all subsequent calls will fail. Ericsson AB cosProperty 1.1.13 CosPropertyService_PropertyNamesIterator(3erl)
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