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Reading password in Unix shell

print -n "Enter Your password:" stty_orig=`stty -g` trap "stty ${stty_orig}; exit" 1 2 3 15 stty -echo >&- 2>&- read PASS stty ${stty_orig} >&- 2>&- trap 1 2 3 15 print

trap :catches interruptions. I.e. if the user presses Ctrl+C, the normal stty mode is set before stopping the program stty -echo :switches off the […]

Unix shell: workaround for loop problem

It’s not possible to get the value of the loop variables in some versions of ksh.


#!/bin/ksh num=0 cat $0 | while read line ; do  let num=num+1 done echo "Number=$num"

This script will return “Number=0” as the result on some Linux machines.

Here is the workaround for the problem: You should change the […]