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Full Discussion: delete all lines in file
Top Forums UNIX for Dummies Questions & Answers delete all lines in file Post 17145 by mikek147 on Monday 11th of March 2002 05:23:03 PM
Old 03-11-2002
touch a_new_empty_file.txt

will create a null file, or will change the last_access_time on that file.

> the_file_I_want_nothing_in.txt

will both empty a full file or create a null file. -mk
 

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Touch(3pm)						User Contributed Perl Documentation						Touch(3pm)

NAME
File::Touch - update access and modification timestamps, creating nonexistent files where necessary. SYNOPSIS
use File::Touch; @file_list = ('one.txt','../two.doc'); $count = touch(@file_list); use File::Touch; $reference_file = '/etc/passwd'; $touch_obj = File::Touch->new( reference => $reference_file, no_create => 1 ); @file_list = ('one.txt','../two.doc'); $count = $touch_obj->touch(@file_list); DESCRIPTION
Here's a list of arguments that can be used with the object-oriented contruction: atime_only => [0|1] If nonzero, change only the access time of files. Default is zero. mtime_only => [0|1] If nonzero, change only the modification time of files. Default is zero. no_create => [0|1] If nonzero, do not create new files. Default is zero. reference => $reference_file If defined, use timestamps from this file instead of current time. Default is undefined. atime => $time If defined, use this time (in epoch seconds) instead of current time for access time. mtime => $time If defined, use this time (in epoch seconds) instead of current time for modification time. Examples Update access and modification times, creating nonexistent files use File::Touch; my @files = ('one','two','three'); my $count = touch(@files); print "$count files updated "; Set access time forward, leave modification time unchanged use File::Touch; my @files = ('one','two','three'); my $day = 24*60*60; my $time = time() + 30 * $day; my $ref = File::Touch->new( atime_only => 1, time => $time ); my $count = $ref->touch(@files); print "$count files updated "; Set modification time back, update access time, do not create nonexistent files use File::Touch; my @files = ('one','two','three'); my $day = 24*60*60; my $time = time() - 30 * $day; my $ref = File::Touch->new( mtime => $time, no_create => 1 ); my $count = $ref->touch(@files); print "$count files updated "; AUTHOR
Nigel Wetters Gourlay (nwetters@cpan.org) COPYRIGHT
Copyright (c) 2001,2007,2009 Nigel Wetters Gourlay. All Rights Reserved. This module is free software. It may be used, redistributed and/or modified under the same terms as Perl itself. perl v5.10.0 2009-07-25 Touch(3pm)
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