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netadmindetail_'s avatar
netadmindetail_
Icon for Nimbostratus rankNimbostratus
Apr 22, 2015

Better way to Cleaning UP string variable

Hi all   I must use the destination FQND of a TCP connection. I'm able to collect the TCP payload but I need to compare it with a data-class. But before doing that I need to clean the TCP payloa...
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  • Sheigh_65772's avatar
    Sheigh_65772
    Apr 22, 2015

    How about using scan?

    If the variable string is set '9net.tcp://sub.domain.com:12345/abcdefg' or 'sometotherstuff9net.tcp://sub.domain.com:12345/abcdefg/lkjsdflkj/sdfl' etc then try using

    scan $string {%*[^/]//%[^:]} fqdn

    this results in a new variable $fqdn of 'sub.domain.com'

    You can test it out by using the tclsh

    % set string "lkasdflkjwe234239net.tcp://sub.domain.com:12345/abcdefg/sdlfkjasf"
lkasdflkjwe234239net.tcp://sub.domain.com:12345/abcdefg/sdlfkjasf
% puts $string
lkasdflkjwe234239net.tcp://sub.domain.com:12345/abcdefg/sdlfkjasf

% scan $string {%*[^/]//%[^:]} fqdn
1
% puts $fqdn
sub.domain.com

    Check out this link: https://devcentral.f5.com/articles/irules-101-18revisiting-the-tcl-scan-command

    FYI I'm just starting to play with scan so YMMV.

    Sheigh

Sheigh_65772's avatar
Sheigh_65772
Icon for Cirrus rankCirrus

Quick time comparison of the two:

% time {  set fqdn [string range $string [expr [string first "://" $string] + 3] [expr [string last ":" $string] - 1]] } 10000
5.7755 microseconds per iteration
% time { scan $string {%*[^:]://%[^:]} fqdn } 10000
1.2681 microseconds per iteration
netadmindetail_'s avatar
netadmindetail_
Icon for Nimbostratus rankNimbostratus
Apr 22, 2015
Wow, thank you very much for this kind of output. Can you tell me how you've been able to grab this information ? Is this the time keyword ? how do you stop the timer ?