Still confused with regex++

From: Mayo (g17mayo_at_[hidden])
Date: 2001-06-11 10:36:55

Hi,

I still have some blank spots in my mind regarding regular 
expressions.

I was going through the documentation of regex++ but I could not find 
a way of creating a regular expression that AND's two strings to be 
searched.

e.g.

Further to what I posted in msg# 12967. 

A message that contains the fields that I am interested to search 
looks like the following:

                  tx_seq_num = 3
                 ack_seq_num = 2
            active_link_flag = 1
          packet_stored_flag = 0
              to_device_type = 1
            to_device_number = 1
            from_device_type = 2
          from_device_number = 2
                 packet_type = 0
             packet_sub_type = 0
         packet_service_type = 0

I want to use a regular expression that can pick two separate fields 
in the above message. For example I wish to search for messages that 
include "tx_seq_num = 3" AND "ack_seq_num = 2" but I am not 
interested to see messages that include only one of the two.

A way I thought was to use an ORed expression 
i.e. "tx_seq_num=3|ack_seq_num = 2" (which works fine btw) and then 
check [what] to see what was matched, if both fields were matched 
then I want to see the message else discard it.

But I am not very sure if in that case the algorithm after finding 
the first match tries to look for the second or returns true with the 
first match (possibly for optimization issues).

I was also wondering what exactly is returned with [what] considering 
that the above message with the ORed expression was a real case 
scenario.

Any help would be appreciated.

Thanks,

George.