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Carl_Weiss_1340's avatar
Carl_Weiss_1340
Icon for Nimbostratus rankNimbostratus
Jun 28, 2016

String Scan question ... trying to do something really simple

Its just not working...   Given a string - "/part1/part2/part3/part4" I want the result to be: p1 = part1 p2 = part2 p3 = /part3/part4   which led me to write the following:   when HTTP_REQU...
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  • Vernon_97235's avatar
    Vernon_97235
    Jun 28, 2016

    String matchers are "greedy", so %s will match everything up to the next whitespace. That's why /%s/%s/%s won't work; everything ends up in $part1.

    The second construct should work. Indeed, on 11.5.4, I do the following:

    when CLIENT_ACCEPTED {
    set path "/foo/bar/baz/bing"
    
    set x [scan $path {/%[^/]/%[^/]/%s} part1 part2 part3]
    if { $x == 3 } {
        log local0. "part1 = $part1; part2 = $part2; part3 = $part3"
    }
    else {
        log local0. "scan returned ($x) elements"
    }
}

    And it works as I expect. In the logs, I get:

    Jun 27 19:00:01 b201 info tmm[13446]: Rule /Common/test_scan : part1 = foo; part2 = bar; part3 = baz/bing
VernonWells's avatar
VernonWells
Icon for Employee rankEmployee
Jun 28, 2016

String matchers are "greedy", so %s will match everything up to the next whitespace. That's why /%s/%s/%s won't work; everything ends up in $part1.

The second construct should work. Indeed, on 11.5.4, I do the following:

when CLIENT_ACCEPTED {
    set path "/foo/bar/baz/bing"
    
    set x [scan $path {/%[^/]/%[^/]/%s} part1 part2 part3]
    if { $x == 3 } {
        log local0. "part1 = $part1; part2 = $part2; part3 = $part3"
    }
    else {
        log local0. "scan returned ($x) elements"
    }
}

And it works as I expect. In the logs, I get:

Jun 27 19:00:01 b201 info tmm[13446]: Rule /Common/test_scan : part1 = foo; part2 = bar; part3 = baz/bing
  • Carl_Weiss_1340's avatar
    Carl_Weiss_1340
    Icon for Nimbostratus rankNimbostratus
    Jul 12, 2016

    sorry for the tardiness - I tried the alternative again and viola! it worked (not sure what happened when I tested it before).