Help with simple scripting actions

Shell Programming and Scripting
1

Hi,

I am a beginner in unix shell scripting.

I wanted simple information like
1- How to know what are the number of command line options given for the script file?

2- How to check if a variable value is interger or string?

3- How to use awk to replace value of a variable
For example I have a file with 5 lines
1
2 ResourceID=ms1
3
4 ResourceID=ms2
5

How can I replace ms1 and ms2 values with other values using awk?

Any site that can give me this information will also be very helpfull.
Thanks!

2

Hi,

regarding Q1:
if your shell supports getopts - I suggest you have a look at it (man getops). Otherwise you will need to write a small shell parsing code. (use $# shell variable that reports the amount of arguments passed to shell script).

regarding Q2:
I would use the following shell code:

expr ${VALUE} + 1 2>/dev/null
if [ $? -eq 0 ]
then
echo "Integer value"
else
echo "String value"
fi

cheers,
Slava R.

3

Regarding Q2, this depends on which shell you are using. It also depends on what an integer is. If 123 +456 -789 all count as integers, and if we are using ksh, I am fond of:

#! /usr/bin/ksh
while (($#)) ; do
        if [[ $1 = ?(+|-)+([0-9]) ]] ; then
                   echo $1 is an integer
        fi
        shift
done
exit 0
4

for Q3. replacing with "hello"

 sed 's/=.*$/=hello/g' file1
5

Thanks!!

Regarding Q3: I meant to replace values ms1 and ms2 with ms3 and ms4.
Using sed or awk, I can assign same value to ResourceID. I couldnt figure out how I can assign different values.

6

Maybe try...

sed -e s/=ms1/=ms3/ -e s/=ms2/=ms4/ file1 > file2