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CRAWL(1)		     General Commands Manual			CRAWL(1)

NAME
     crawl -- a small and efficient HTTP crawler

SYNOPSIS
     crawl [-u urlincl] [-e urlexcl] [-i imgincl] [-I imgexcl] [-d imgdir]
	   [-m depth] [-c state] [-t timeout] [-A agent] [-R] [-E external]
	   [url ...]

DESCRIPTION
     The  crawl  utility starts a depth-first traversal of the web at the speci-
     fied URLs.  It stores all	JPEG  images  that  match  the	configured  con-
     straints.

     The options are as follows:

     -v level	  The  verbosity  level of crawl in regards to printing informa-
		  tion about URL processing.  The default is 1.

     -u urlincl   A regex(3) expression that all URLs that should be included in
		  the traversal have to match.

     -e urlexcl   A regex(3) expression that determines which URLs will  be  ex-
		  cluded from the traversal.

     -i imgincl   A regex(3) expression that all image URLs have to match in or-
		  der to be stored on disk.

     -I imgexcl   A regex(3) expression that determines the images that will not
		  be stored.

     -d imagedir  Specifies the directory under which the images will be stored.

     -m depth	  Specifies  the maximum depth of the traversal.  A 0 means that
		  only the URLs specified on the command line will be retrieved.
		  A -1 stands for unlimited traversal and should  be  used  with
		  caution.

     -c state	  Continues a traversal that was interrupted previosly.  The re-
		  maining URLs with be read from the file state.

     -t timeout   Specifies  the time in seconds that needs to pass between suc-
		  cessive access of a single host.  The parameter  is  a  float.
		  The default is five seconds.

     -A agent	  Specifies  the  agent string that will be included in all HTTP
		  requests.

     -R 	  Specifies that the crawler should ignore the robots.txt file.

     -E external  Specifies an external filter program	that  can  refine  which
		  URLs	are to be included in the traversal.  The filter program
		  reads the URLs on stdin and  outputs	a  single  character  on
		  stdout.   An	output	of `y' indicates that the URL may be in-
		  cluded, `n' means that the URL should be excluded.

     The source code for existing web crawlers	tend  to  be  very  complicated.
     crawl is a very simple design with pretty simple source code.

     A	configuration  file  can  be used instead of the command line arguments.
     The configuration file contains the MIME-type that is being used.	To down-
     load other objects besides images the MIME-type needs to  be  adjusted  ac-
     cordingly.  For more information, see crawl.conf.

EXAMPLES
     crawl -m 0 http://www.w3.org/

     Searches  for  images in  the index page of the web consortium without fol-
     lowing any other links.

ACKNOWLEDGEMENTS
     This product includes software developed by Ericsson Radio Systems.

     This product includes software developed by the University  of  California,
     Berkeley and its contributors.

AUTHORS
     The crawl utility has been developed by Niels Provos.

FreeBSD ports 15.quarterly	  May 29, 2001				CRAWL(1)

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