Re: if variable is not set....

Timothy Luoma asked,

| Perhaps I'm just too sleepy to figure this out, but how can I do this:

| if [ "$VAR1" = "" ]
| then
|       OTHERVAR=x
| else
|       OTHERVAR=y
| fi

Now, here's the question, Timothy: your subject line speaks of a variable's
not being set, but the sample sh code you gave treats a null (but set) vari-
able the same as an unset one.

To emulate in procmailrc language what you have written there,

 :0
 * VAR1 ?? ^^^^
 { OTHERVAR=x }
 :0E
 { OTHERVAR=y }

or equivalently,

 :0
 * $ ${VAR1:+!}
 { OTHERVAR=x }
 :0E
 { OTHERVAR=y }

but if you really want to assign OTHERVAR=x only if VAR1 is unset (and y
if VAR1 is set, even if VAR1 is null), you need to do this [note the absence
of a colon in the condition]:

 :0
 * $ ${VAR1+!}
 { OTHERVAR=x }
 :0E
 { OTHERVAR=y }

| So I put the real LASTFOLDER into another variable called REALFOLDER and  
| want to use
| 
| TRAP='\
| echo "\
| _________ NEW $TYPE MESSAGE FROM: $FROM
| To/Cc   $TO / $CC
| Subject $SUBJECT
| Date    $DATE
| Size     $SIZE
| ID      $ID
| _________ MESSAGE WENT TO:  $LASTFOLDER
| "'
| 
| to log.... However, if "REALFOLDER" has a value, then I want to use the  
| value of REALFOLDER for LASTFOLDER in the TRAP statement.

Just change $LASTFOLDER to ${REALFOLDER-$LASTFOLDER} in your trap:

TRAP='\
echo "\
_________ NEW $TYPE MESSAGE FROM: $FROM
To/Cc   $TO / $CC
Subject $SUBJECT
Date    $DATE
Size     $SIZE
ID      $ID
_________ MESSAGE WENT TO:  ${REALFOLDER-$LASTFOLDER}
"'