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Positional Parameters

 
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# 8  
Old 10-22-2005
Code:
mail $mailtolist < testing

# 9  
Old 10-22-2005
Code:
# The following commented lines do not work.
# Is it because I am using the Bourne Shell?
# if["$1"!=""];
# then echo "Positional parameter 1 contains something."
# else echo "Positional parameter 1 is empty."
# fi

The if statement should be as

Code:
if [ "$1" != "" ] ;

Notice the white space.

Code:
mail mailtolist < testing

It should be

Code:
mail $mailtolist < testing

Code:
Is it possible for the mailtolist variable to contain more than one e-mail address?

Yes.
Code:
user1="a@b.com"
mailtolist=$user1
user2="user@user.com"
mailtolist="$mailtolist $user2"

# 10  
Old 10-22-2005
Quote:
The if statement should be as

if [ "$1" != "" ] ;

Notice the white space.
I had the whitespace in the first time I tried it. I took the whitespace out to see if that made a difference, but it did not make a difference.


Quote:
It should be

mail $mailtolist < testing
Ah ha. Thank you!

Quote:
user1="a@b.com"
mailtolist=$user1
user2="user@user.com"
mailtolist="$mailtolist $user2"
OK, that makes sense. Would that be the same as:
Code:
mailtolist="a@b.com user@user.com"

?

Thank you,
Eric
# 11  
Old 10-22-2005
Replace
Code:
if [ "$1" != "" ] ;

with
Code:
if [ ! -z "$1" ] ; then
echo "Arguments available"
fi ;

Read man test for the construct -z and others.

And yes,
Code:
mailtolist="a@b.com user@user.com"

is the same as the previous suggestion.
# 12  
Old 10-22-2005
Quote:
if [ ! -z "$1" ]
-z string
True if the length of string string is zero.

So the statement above is saying,
if[ the length of string string is not zero]

Am I understanding this correctly? Is that really what the if statement needs to test?

Thanks,
Eric
# 13  
Old 10-22-2005
Quote:
Originally Posted by ericelysia
Is that really what the if statement needs to test?
What the if statement needs to test depends on what you want it to.

That was given for a workaround for the following case.

Code:
if[ "$1" != "" ] ;
then echo "Positional parameter 1 contains something."
else echo "Positional parameter 1 is empty."
fi

This should make it clear.

Code:
if [ ! -z "$1" ] ; then
echo "Positional parameter 1 contains something."
else
echo "Positional parameter 1 is empty."
fi ;

# 14  
Old 10-22-2005
OK, I don't know why I was making that more complicated than it is.

I was letting the "not" confuse me.

Now I understand.

Thank you,
Eric
 
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