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up vote 1 down vote favorite

Today, I have to check the existence and the number of input arguments. I have the following script:

#!/bin/bash

echo "*** Test ***"
echo
echo $#
echo $*

function test1(){
   echo "test"
}

if [ "$#" -ne 1 ]; then
    echo "Illegal number of parameters"
else
    test1   
fi

function GetTime()
{
   echo "Get Time function"
   if [ "$#" -ne 1 ]; then
       echo "Illegal number of parameters"
   else
       test1
   fi
}

When I enter ./test.sh GetTime I get 

*** Test ***

1
GetTime
test
Get Time function
Illegal number of parameters

I do not understand why the behavior is different between the first condition and the one contains within the GetTime() function. Somebody could help me ?

Thank in advance

share|improve this question
5  
Have you missed posting some of your script? How is GetTime() even being called? – GreenAsJade Nov 17 '14 at 15:03
1  
Since when are bash functions defined using a function keyword? – Géza Török Nov 17 '14 at 16:16

1 Answer 1

up vote 3 down vote accepted

It is different because $# in first if refer to the number of arguments to the shell script. Where as the $# in second indicates the number of argument to GetTime function

To understand more I have modified the GetTime function as

#!/bin/bash

echo "*** Test ***"
echo
echo $#
echo $*

function test1(){
   echo "test"
}

if [ "$#" -ne 1 ]; then
    echo "Illegal number of parameters"
else
    test1   
fi

function GetTime()
{
   echo "Get Time function"
   echo "$# $@"
   if [ "$#" -ne 1 ]; then
       echo "Illegal number of parameters"
   else
       test1
   fi
}

GetTime 
GetTime 2

Giving output as

*** Test ***
1
GetTime
test
Get Time function
0 
Illegal number of parameters
Get Time function
1 2
test

Here for the first call GetTime gives

Get Time function
0 
Illegal number of parameters

Where 0 is the number of parameters passed

and Second call as GetTime 2

produced output

Get Time function
1 2
test

Where 1 is the number of parameters passed and 2 is the argument itself

share|improve this answer
    
But GetTime() isn't getting called anywhere. – anubhava Nov 17 '14 at 15:07
    
@anubhava Op might have missed it. I dont think the output is obtainable without a call to GetTime() – nu11p01n73R Nov 17 '14 at 15:16
    
Thank a lot for the clarification ! – SnP Nov 17 '14 at 15:57
    
@SnP You are welcome :) – nu11p01n73R Nov 17 '14 at 15:57

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