Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
LOOP(1)				    BRL-CAD			       LOOP(1)

NAME
       loop - generate numerical indices for shell loops, etc.

SYNOPSIS

       loop [-c] start finish [increment]

DESCRIPTION
       loop generates a	sequence of numbers between start and finish
       inclusive, one per line,	on stdout. This	is mostly useful for driving
       loops when writing Shell	programs sh(1).	The default increment is +1
       when start<finish, and -1 when start>finish. An optional	increment may
       be specified. If	increment is zero, then	the start value	will be
       generated continuously.

       Both floating point and integer arguments can be	used. On integer
       arguments, if leading zeros are specified, they will be preserved on
       output. This is useful for generating sequences of file names which are
       numbered	with leading zeros.

       -c is used for character	(char) looping.

EXAMPLES
	   for i in `loop 10 30	5`
	   do
	     echo $i
	   done

       will display the	values 10, 15, 20, 25, 30 .

	   for i in `loop 008 005`
	   do
	     echo $i
	   done

       will display the	values 008, 007, 006, 005 .

	   for i in `loop 0.1 2.9 0.5`
	   do
	     echo $i
	   done

       will display the	values 0.1, 0.6, 1.1, 1.6, 2.1,	2.6 .

BUGS
       This program just scratches the surface.	The shells could benefit from
       a greater ability to perform math. Limitless opportunities for
       extensions exist, but this simple version is adequate for most shell
       scripts dealing with sequences of images, etc.

AUTHOR
       BRL-CAD Team

COPYRIGHT
       This software is	Copyright (c) 1986-2021	by the United States
       Government as represented by U.S. Army Research Laboratory.

BUG REPORTS
       Reports of bugs or problems should be submitted via electronic mail to
       devs@brlcad.org

BRL-CAD				  04/13/2025			       LOOP(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=loop&sektion=1&manpath=FreeBSD+Ports+14.3.quarterly>

home | help