UNIX for Dummies Questions & Answers

Hello,

i have a problem. I must write a script, which wants 2 arguments.

for example:

it must be write x.txt in y.txt

and when i give 1 or no argument like

must this give a error message like: SYNTAX <inputfile> <outputfile>

my solution is this:
but it does work, and i know that i do something false but what??

thanks

you are not closing the if statement

Code:

if [ "${1}" ]; then
 echo args is: "${1}"
else
 echo -e "SYNTAX <inputfile> <outputfile>"
fi
if [ "${2}" ]; then
 echo args is: "${2}"
else
 echo -e "SYNTAX <inputfile> <outputfile>"
fi

or try this

Code:

#!/bin/ksh
if [[ ${1} -ne "" && ${2} -eq "" ]]; then
 echo args is: "${1}"
 echo -e "SYNTAX <inputfile> <outputfile>"
elif [[ ${1} -eq "" ]]; then
 echo -e "SYNTAX <inputfile> <outputfile>"
fi

Quick question here: why not just use cp?

I thought he want to do some other stuff

thx but i write a script too, but it doesnt work fine.

when i give 2 arguments then it works but when i give 1 or no argument, then gives it error messages.
1. error message is that touch operand is missing
2.error message is: line 26 : $2 : ambigous redirect


sorry i am a beginner

Since you refer to a second parameter in your script, it needs 2 parameters to successfully run, but this isn't checked for anywhere. If you wrap it as below, then it will fail gracefully if the wrong number of parameters are given (none, one, or 3+).

Code:

if [ $# = 2 ]
then {
     your code here
}
else {
     echo -e "SYNTAX: $0 <IN> <OUT>"
}
fi;

If you want a different case for 1 parameter, then you can add another statement like if [ $# = 1] for 1 parameter, etc. or put it in a case of $# ($# is the number of parameters, if that isn't obvious from the example.)