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# 1  
Old 10-04-2010
Check input parameter

Hi all

i need to check that if user has passed any input parameter while executing he shell script like

./ -a"-v"

then do smothing

if user execute the script without giving input paramater then


then do something

how can we check this input parameter

Last edited by Scott; 10-04-2010 at 11:39 AM.. Reason: Code tags
# 2  
Old 10-04-2010


u can get the parameters in $ variable....
FYI: $0 is the script name itself
# 3  
Old 10-04-2010
if [[ $# -gt 1 ]]
        do something
        do some-other thing

Include this in your script for which the input parameters needs to be checked.

$# -- holds the number of arguments passed to the script
# 4  
Old 10-04-2010
For a thorough checking of options and arguments you might want to use the "getopts" program or - depending on your shell - the getopts built-in respectively.

For checks on datatypes (like "string", "integer", "filename", etc.) of arguments you might read the following posts:

I hope this helps.

# 5  
Old 10-04-2010
hi everyone
thanx for your help
i have one more query
suppose if user can enter parameter only like this

./ -a"-v"

there is no space between -a and "-v" then if we have to follow two operation based on parameter passed like

./ -a


./ -a"-v"

then i suppose we cannot take $1 and $2 because for that we must have space between them
then how we will solve this

Last edited by Scott; 10-04-2010 at 11:39 AM.. Reason: Code tags
# 6  
Old 10-04-2010

I think that problem goes away with getopts:

$ cat testscript
while getopts a: ARG; do
  case "$ARG" in
    a)  echo "OPTARG is $OPTARG"

$ ./testscript -a" -v"

OPTARG is  -v

Not exactly clear what you're getting at, though, or why.
# 7  
Old 10-04-2010
hi aishsimplesweet
In your case, shell script can have only one argument i.e $1

what you can do is declare a variable var=$1
then split based on delimiter. (i.e ")

Let us know the complete functionality of the code so that it can be implemented accordingly

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