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Full Discussion: Perl:How to insert a line to a file.
Top Forums Shell Programming and Scripting Perl:How to insert a line to a file. Post 302480351 by citaylor on Tuesday 14th of December 2010 03:44:39 PM
Old 12-14-2010
Im afraid you cannot simply insert lines into a file in this manner - you have to either read the whole file into memory and write back the new file, or you have to write the output to a temporary file.
Here is an example of the former...
Code:
#!/usr/bin/perl
open(FILE,"foo.txt") || die "can't open file for read\n"; 
my @lines=<FILE>;
close(FILE);
open(FILE,">foo.txt")|| die "can't open file for write\n";
foreach $line (@lines) {
    if($line =~ /AAA/) {
        print FILE "CCC\n";
    } else {
        print FILE $line;
    }
}#end foreach
close(FILE);

Last edited by citaylor; 12-14-2010 at 04:45 PM.. Reason: typo
 

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LEARN ABOUT DEBIAN

pdf2txt

PDF2TXT(1)							  PDFMiner Manual							PDF2TXT(1)

NAME

       pdf2txt - extracts text contents of PDF files

SYNOPSIS

       pdf2txt [option...] file...

DESCRIPTION

       pdf2txt extracts text contents from a PDF file. It extracts all the text that is to be rendered programmatically, i.e. text represented as
       ASCII or Unicode strings. It cannot recognize text drawn as images that would require optical character recognition. It also extracts the
       corresponding locations, font names, font sizes, writing direction (horizontal or vertical) for each text portion. You need to provide a
       password for protected PDF documents when its access is restricted. You cannot extract any text from a PDF document which does not have
       extraction permission.

OPTIONS

       -o file
	   Specifies the output file name. The default is to print the extracted contents to standand output in text format.

       -p pageno[,pageno,...]
	   Specifies the comma-separated list of the page numbers to be extracted. Page numbers start at one. By default, it extracts text from
	   all the pages.

       -c codec
	   Specifies the output codec.

       -t type
	   Specifies the output format. The following formats are currently supported:

	   text
	       Text format. This is the default.

	   html
	       HTML format. It is not recommended.

	   xml
	       XML format. It provides the most information.

	   tag
	       "Tagged PDF" format. A tagged PDF has its own contents annotated with HTML-like tags.  pdf2txt tries to extract its content streams
	       rather than inferring its text locations. Tags used here are defined in the PDF Reference, Sixth Edition[1] (S10.7 "Tagged PDF").

       -D writing-mode
	   Specifies the writing mode of text outputs:

	   lr-tb
	       Left-to-right, top-to-bottom.

	   tb-rl
	       Top-to-bottom, right-to-left.

	   auto
	       Determine writing mode automatically

       -M char-margin, -L line-margin, -W word-margin
	   These are the parameters used for layout analysis. In an actual PDF file, text portions might be split into several chunks in the
	   middle of its running, depending on the authoring software. Therefore, text extraction needs to splice text chunks. In the figure
	   below, two text chunks whose distance is closer than the char-margin is considered continuous and get grouped into one. Also, two lines
	   whose distance is closer than the line-margin is grouped as a text box, which is a rectangular area that contains a "cluster" of text
	   portions. Furthermore, it may be required to insert blank characters (spaces) as necessary if the distance between two words is greater
	   than the word-margin, as a blank between words might not be represented as a space, but indicated by the positioning of each word.

	   Each value is specified not as an actual length, but as a proportion of the length to the size of each character in question. The
	   default values are char-margin = 1.0, line-margin = 0.3, and W = 0.2, respectively.

       -n
	   Suppress layout analysis.

       -A
	   Force layout analysis for all the text strings, including text contained in figures.

       -V
	   Enable detection of vertical writing.

       -s scale
	   Specifies the output scale. This option can be used in HTML format only.

       -m n
	   Specifies the maximum number of pages to extract. By default, all the pages in a document are extracted.

       -P password
	   Provides the user password to access PDF contents.

       -d
	   Increase the debug level.

EXAMPLES

       Extract text as an HTML file whose filename is output.html:

	   $ pdf2txt -o output.html samples/naacl06-shinyama.pdf

       Extract a Japanese HTML file in vertical writing:

	   $ pdf2txt -c euc-jp -D tb-rl -o output.html samples/jo.pdf

       Extract text from an encrypted PDF file:

	   $ pdf2txt -P mypassword -o output.txt secret.pdf

SEE ALSO

       dumppdf(1)

AUTHORS

       Jakub Wilk <jwilk@debian.org>
	   Wrote this manual page for the Debian system.

       Yusuke Shinyama <yusuke@cs.nyu.edu>
	   Author of PDFMiner and its original HTML documentation.

NOTES

	1. PDF Reference, Sixth Edition
	   http://www.adobe.com/devnet/acrobat/pdfs/pdf_reference_1-7.pdf

pdf2txt 							    08/24/2011								PDF2TXT(1)
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