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Full Discussion: Diamond operator in Until Statement (perl)
Top Forums Shell Programming and Scripting Diamond operator in Until Statement (perl) Post 302267492 by otheus on Friday 12th of December 2008 01:09:05 PM
Old 12-12-2008
Back to your original question (which you think you solved)...

Quote:
Originally Posted by erichpowell
Code:
            print $2;
            my $nxtLine = <$IN>;
            until ($nxtLine =~ /(-!-)/) {
                $nxtLine =~ /CC *(.*)/;
                print $1;
                $nxtLine = <$IN>;

First, I recommend against using a $ inside a file descriptor ($IN). This makes it look like something is happening that isn't: namely, file descriptors ARE NOT SCALAR VARIABLES in Perl. They are a class of variables in their own right. What's really happening is, I think, $IN is evaluating into undef, so that you have:
Code:
 while (<>) { 
...
 my $nxtLine = <>;

and so on.

As you noted, the <> is an operator that reads a line from the filedescriptor in between the brackets, or if none given, from the next command given on the command line, or if none are present, from STDIN (standard input, that is, piped or redirected input).

So $IN I think is going to make things confusing. Just use "IN" here.

Or, better yet,use the command line and the aforementioned feature:
[code]
$ your_perl_script.pl Batch*
[code]
And in your code:
Code:
while (<>) { 
...
 my $nxtLine = <>;
...

 

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LEARN ABOUT ULTRIX

compact

compact(1)						      General Commands Manual							compact(1)

Name
       compact, uncompact, ccat - compress and uncompress files, and cat them

Syntax
       compact [name...]
       uncompact [name...]
       ccat [file...]

Description
       The  command compresses the named files using an adaptive Huffman code.	If no file names are given, the standard input is compacted to the
       standard output.  The command operates as an on-line algorithm.	Each time a byte is read, it is encoded immediately according to the  cur-
       rent  prefix  code.   This code is an optimal Huffman code for the set of frequencies seen so far.  It is unnecessary to prepend a decoding
       tree to the compressed file since the encoder and the decoder start in the same state and stay synchronized.  Furthermore, and can  operate
       as filters.  In particular,
	    ... | compact | uncompact | ...
       operates as a (very slow) no-op.

       When  an  argument file is given, it is compacted and the resulting file is placed in file.C; file is unlinked.	The first two bytes of the
       compacted file code the fact that the file is compacted.  This code is used to prohibit recompaction.

       The amount of compression to be expected depends on the type of file being compressed.  Typical values of compression are: Text (38%), Pas-
       cal Source (43%), C Source (36%) and Binary (19%).  These values are the percentages of file bytes reduced.

       The command restores the original file from a file compressed by If no file names are given, the standard input is uncompacted to the stan-
       dard output.

       The command cats the original file from a file compressed by without uncompressing the file.

       The command is present only for compatibility.  In general, the command runs faster and gives better compression.

Restrictions
       The last segment of the file name must contain fewer than thirteen characters to allow space for the appended '.C'.

Files
       compacted file created by compact, removed by uncompact

See Also
       compress(1)

																	compact(1)
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