mbeason has asked for the wisdom of the Perl Monks concerning the following question:

Fellow Monks.. I'm trying to do a simple file test on each file in an array. However, I never get any results back. If I put a print statement before the file test, I get the expected results. Once the file test is in place, nothing happens. Here is my code.. 
foreach (@test_node_list) {
    if (-e "/usr/adm/best1_default/collect/$_/noInstance") { # It prob
+ably is a node with data
        if (-e "/usr/adm/best1_default/manager/$_") {        # It has 
+a vis files directory
            @node_list = (@node_list,$_);
            if (-e "/usr/adm/best1_default/manager/$_/$vis_year$vis_mo
+nth$vis_zero$vis_day*.vis") {
                system("/appl/perform/best1home/perl/clean_graphics.pl
+", "$_");
                print "It exists.\n";
            }
        }
     }
}

[download]
The part that dies the piece just after the @node_list array. Your guidance is always appreciated!

Replies are listed 'Best First'.
Re: Simple File Test
by Zaxo (Archbishop) on Jul 11, 2006 at 23:03 UTC

    Try placing, 

    print "/usr/adm/best1_default/manager/$_/$vis_year$vis_month$vis_zero$
+vis_day*.vis\n";

    [download]
    before the test. Is that what you expect it to be? I suspect it appears to die because you get no match, and there is nothing following to indicate life. '*' is an uncommon character to find in a file name, since it conflicts with shell glob. Do you want a glob there, instead of -e?

    After Compline,
    Zaxo

[reply]
[d/l]
Re: Simple File Test
by kwaping (Priest) on Jul 11, 2006 at 23:05 UTC
    I recommend inserting the following line right after the line containing @node_list: 
    print "/usr/adm/best1_default/manager/$_/$vis_year$vis_month$vis_zero$
+vis_day*.vis";

    [download]
    Also, @node_list = (@node_list,$_); is better written as push @node_list, $_;.

    ---
    It's all fine and dandy until someone has to look at the code.
[reply]
[d/l]
[select]
      I've made the change to the code.. Here it is: 
       
foreach (@test_node_list) {
    if (-e "/usr/adm/best1_default/collect/$_/noInstance") { # It prob
+ably is a node with data
        if (-e "/usr/adm/best1_default/manager/$_") {        # It has 
+a vis files directory
            push @node_list, $_;
            if (-e "/usr/adm/best1_default/manager/$_/$vis_year$vis_mo
+nth$vis_zero$vis_day*.vis") {
                print;
        }
     }
}

      [download]
      This doesn't generate anything. I realize the filename looks odd but when I check them from the cmdline, it works as expected. I'm trying to say, "If this node has a file called X, then do something. Right now, I just have a print statement there. Eventually, I really want to put a system() instead.
[reply]
[d/l]
        I realize the filename looks odd but when I check them from the cmdline, it works as expected.

        You need to expand on what you mean by "check them from the cmdline". If you're saying when you run ls /usr/adm/best1_default/manager/foo/20060711*.vis it shows files, then you've missed what was being said about needing to use glob. Your shell will expand the wildcard *, the -e operator (among other things) will not. If you want wildcard expansion you need to use glob, or do something like using opendir and then grep'ing the results from a readdir.

[reply]
[d/l]
        You've misunderstood. Here's the actual code with our suggested edits: 
        foreach (@test_node_list) {
    if (-e "/usr/adm/best1_default/collect/$_/noInstance") { # It prob
+ably is a node with data
        if (-e "/usr/adm/best1_default/manager/$_") {        # It has 
+a vis files directory
            push @node_list, $_;
            print "/usr/adm/best1_default/manager/$_/$vis_year$vis_mon
+th$vis_zero$vis_day*.vis";
            if (-e "/usr/adm/best1_default/manager/$_/$vis_year$vis_mo
+nth$vis_zero$vis_day*.vis") {
                system("/appl/perform/best1home/perl/clean_graphics.pl
+", "$_");
                print "It exists.\n";
            }
        }
     }
}

        [download]

        ---
        It's all fine and dandy until someone has to look at the code.
[reply]
[d/l]

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