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Full Discussion: Need help deciphering this
Top Forums UNIX for Dummies Questions & Answers Need help deciphering this Post 302417172 by Scott on Wednesday 28th of April 2010 06:44:25 PM
Old 04-28-2010
Hi.

The brackets (braces) are backslashed to give them special meaning (they would otherwise be literal braces).

^ matches something at the beginning of the line (an empty string because it doesn't remove anything from the pattern space), but has special meaning if it's the first character after a square braclet [ (in which case it negates the match (i.e. ^[0-9] means match a number at the start of a line, whereas ^[^0-9] means don't match a number at the start of a line, and [^0-9] means don't match a number, wherever [^0-9] appears in your expression).

In your expression ^.\{42\} means match 42 of any character starting at the beginning of the line, as DrSammy described.
Last edited by Scott; 04-28-2010 at 07:50 PM.. Reason: typo
 

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LEARN ABOUT DEBIAN

tv_split

TV_SPLIT(1p)						User Contributed Perl Documentation					      TV_SPLIT(1p)

NAME

       tv_split - Split XMLTV listings into separate files by date and channel.

SYNOPSIS

       tv_split --output TEMPLATE [FILE...]

DESCRIPTION

       Read XMLTV listings and split them into some number of output files.  The output file chosen for each programme is given by substitutions
       on the filename template supplied.  You can split listings by time and by channel.

       The TEMPLATE is a filename but substitutions are applied: first %channel is replaced with the id of a programme's channel, and then
       Date::Manip substitutions (which broadly follow date(1)) are applied based on the start time of each programme.	In this way each programme
       is written to a particular output file.	When an output file is created it will also contain all the channel elements from the input.

       One or more input files can be given; if more than one then they are concatenated in the same way as tv_cat.  If no input files are given
       then standard input is read.

EXAMPLE

       Use "tv_split --output %channel-%Y%m%d.xml" to separate standard input into separate files for each day and channel.  The files will be
       created with names like bbc1.bbc.co.uk-20020330.xml.

SEE ALSO

       Date::Manip(3).

AUTHOR

       Ed Avis, ed@membled.com.

perl v5.14.2							    2004-01-20							      TV_SPLIT(1p)
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