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Function call with argument doubt

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# 1  
Old 08-28-2009
Error Function call with argument doubt
Hi all,

I am having a problem with user defined function call. I am new into the concept of shell script UDFs.

My function is:
Code:
iterate_directory()
{
cd $1
k=0
for i in *
    do
        if [ -d "$i" ]
        then
            ARR[k++]=${i}
        fi
    done
echo ${ARR[*]}
}

This is for iterate a directory and stored all sub-directories in an array

I called this function like this
Code:
directory="/tmp/"
array1=iterate_directory "$directory"

Please correct me, where I went wrong.
# 2  
Old 08-28-2009
Hi,

You forgot to mention the shell you are using. Assigning a value to an array by calling a function does not work. Neither in bash or in ksh. As bash and ksh function variable scope is global by default, your array ARR is visible outside your function.
# 3  
Old 08-28-2009
Quote:
Originally Posted by ripat
Hi,

You forgot to mention the shell you are using. Assigning a value to an array by calling a function does not work. Neither in bash or in ksh. As bash and ksh function variable scope is global by default, your array ARR is visible outside your function.
Oh, I am sorry.

I am using bash shell
Code:
GNU bash, version 3.2.48(1)-release (i486-pc-linux-gnu)
Copyright (C) 2007 Free Software Foundation, Inc.

if I drop that echo in my function is it going to work ?
Last edited by canishk; 08-28-2009 at 03:40 AM..
# 4  
Old 08-28-2009
No, as
Quote:
Originally Posted by canishk
Code:
array1=iterate_directory "$directory"

is not correct. You can not assign a value to an array that way as the function only returns a code, not a value.
Just do something like this:
Code:
iterate_directory()
{
cd $1
k=0
for i in *
    do
        if [ -d "$i" ]
        then
            array1[k++]=${i}
        fi
    done
}

# 5  
Old 08-28-2009
Power
Quote:
Originally Posted by ripat
No, as

is not correct. You can not assign a value to an array that way as the function only returns a code, not a value.
Just do something like this:
Code:
iterate_directory()
{
cd $1
k=0
for i in *
    do
        if [ -d "$i" ]
        then
            array1[k++]=${i}
        fi
    done
}

So there is no use of functions, if there is no means of re-usability then what is the need of functions ?Smilie
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