Shell Programming and Scripting

##!/bin/bash
## userprocesses 
#Display actual users name 

	who | wc -l > nousers
	set -- cut -f1 nousers
	numberusers=$1

Code:

numberusers=$( who | wc -l )

	usercnt=1 # counter used in setup
	pos=1 # position in array
	outcount=1 # counter used in getname method
	userout=1 # set for output 

		who -q > tempA
		set -- $( cut -f "$pos" tempA); 

 while [ "$usercnt" -le "$numberusers" ]
do
		eval user${pos}=$1
		shift
		usercnt='expr usercnt + 1'
		pos='expr pos + 1'

You don't need expr in bash; expr is an external command (i.e., it's slow), and bash (like all POSIX shells) has integer arithmetic built in:

Code:

usercnt=$(( $usercnt + 1 ))
pos=$(( $pos + 1 ))

If you do use expr, you need to give it the contents of the variables, not their names (e.g., $usercnt, not usercnt).

The whole operation can be done much more efficiently by reading the output of who directly:

Code:

who | while read name junk
do
   : do whatever
done

If you want to put the names into an array, use bash's built-in arrays:

Code:

names=( who | cut -d ' ' -f1 )
: