[Asterisk-Users] Parsing a variable, or rather Splitting a variable

[Hadar Pedhazur]

Derek, this is great, thanks much! I can definitely make this work for 
me, but in practice, my problem is a little more complex, and on the 
off chance that there is a solution, I'll state it. Otherwise, I can 
work around it (I think).

Here's an example of what my input looks like (in reality, it's even 
worse than this, because there are 3 or 4 variable length channels):

ChanIsAvail(SIP/2001&IAX2/abc at xyz)

So, a fixed length substring won't really work for me. Of course, 
worst case scenario here I can test the substring first for whether it 
starts with SIP or IAX2 (for the above), and then branch accordingly. 
That's not too bad (logic-wise), but it adds a number of steps to the 
dialplan that perhaps could be avoided if there was a 
"Split(String,'-',1)" (for example, to pick out the first token)...

Thanks again, since I'm now all set even if my particular needs can't 
be met "directly". :-)

Derek Bruce wrote:
> given:
> exten => 2001,1,ChanIsAvail(SIP/2001&SIP/3001)
> exten => 2001,2,SubString,ToDial=${AVAILCHAN}|0|8
> exten => 2001,3,Dial(${ToDial},20)
> 
> you know that your dialstring will be 'SIP/2001', your technology prefix
> ('SIP/' 4 characters) length plus your extention length (4 characters) = 8
> characters... a fixed length...
> 
> for a variable length extention use:
> exten => _1.,1,ChanIsAvail(SIP/$EXTEN})
> exten => _1.,2,SubString,ToDial=${AVAILCHAN}|0|${LEN(EXTEN)}+4 )
> exten => _1.,3,Dial(${ToDial},20)
> 
> ----- Original Message -----
> From: "Hadar Pedhazur" <hadar at unorthodox.com>
> To: <Asterisk-Users at lists.digium.com>
> Sent: Tuesday, March 09, 2004 3:25 PM
> Subject: [Asterisk-Users] Parsing a variable, or rather Splitting a variable

>>The wiki page on ChanIsAvail says:
>>
>>"Thus, if you are going to use the value of AVAILCHAN, you need to
>>strip the session ID off."
>>
>>I understand why this is necessary (from seeing what is returned in
>>the CLI), but I don't see any commands that can accomplish this since
>>the session id after the "-" is of variable length (so you can't use
>>":" notation, or StripLSD, etc.).
>>
>>I would like to avoid making an external AGI call if possible, and I'm
>>hoping I'm just missing something obvious here.
>>
>>Thanks in advance!