RE: [WEB400] Using Varying

[Jim Langston <jlangston@xxxxxxxxxxx>]

Read Hans post.

Here is a little more explanation so you understand what Hans means.

Basically, a varying string has to know how long the string is, right?  Well, 
it stores that information in two "hidden" bytes, ones we never really see.  
That are the two first bytes of the string.  Normally, we don't care.  We as 
for the value of the string, and RPG looks at the two hidden bytes, figures the 
length, and returns the string starting at the 3rd byte for that length.

So, say MyVarying contains 'Hi'.
What the MyVarying variable actually contains is something similar to:
1st Byte: 0
2nd Byte: 2
3rd Byte: 'H'
4th Byte: 'i'

the length may be encoded some other way, it really doesn't matter for this 
explanation.

Now, the problem is when you pass a varying string to a function that expects a 
fixed length string.

     c                   eval      htmlOut = x'15' +
     C                             '<UL>'
     c                   eval      outLn = %len(%trim(htmlOut))
     c                   callb     'QtmhWrStout'
     c                   parm                    htmlOut
     c                   parm                    outln
     c                   parm                    qusec

htmlOut is being passed something like x'0' x'5' + '<UL>'
with the initial bytes of 0 and 5 being the length of the string, that's the 
garbage you're seeing.

So, you actually want to pass the string x'15' + '<UL>' that starts in byte 3 
of the varying variable.  So Hans has two "tricks" to do this.

The 3rd option is to, as you stated, move the varying string into a fixed 
length string before the call, but Hans solution is, IMO, much better.

Regards,

Jim Langston

-----Original Message-----
From: MWalter@hanoverwire.com [mailto:MWalter@hanoverwire.com]

Jim,

Here is a code snippit,

     DhtmlOut          S           1024    VARYING
     Dx                s             10i 0

     c                   clear                   htmlOut
     c                   eval      htmlOut = x'15' +
     C                             '<UL>'
     C**                           '<TABLE border="1">'
     c                   eval      outLn = %len(%trim(htmlOut))
     c                   callb     'QtmhWrStout'
     c                   parm                    htmlOut
     c                   parm                    outln
     c                   parm                    qusec
<SNIP>