1.\" $NetBSD: expand.1,v 1.11 2008/12/21 02:33:13 christos Exp $ 2.\" 3.\" Copyright (c) 1980, 1990, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)expand.1 8.1 (Berkeley) 6/9/93 31.\" 32.Dd December 20, 2008 33.Dt EXPAND 1 34.Os 35.Sh NAME 36.Nm expand , 37.Nm unexpand 38.Nd expand tabs to spaces, and vice versa 39.Sh SYNOPSIS 40.Nm 41.Op Fl t Ar tabstop 42.Op Fl t Ar tab1,tab2,...,tabn 43.Op Ar 44.Nm unexpand 45.Op Fl a 46.Op Fl t Ar tab1,tab2,...,tabn 47.Op Ar 48.Sh DESCRIPTION 49.Nm 50processes the named files or the standard input writing 51the standard output with tabs changed into blanks. 52Backspace characters are preserved into the output and decrement 53the column count for tab calculations. 54.Nm 55is useful for pre-processing character files 56(before sorting, looking at specific columns, etc.) that 57contain tabs. 58.Pp 59If a single 60.Ar tabstop 61argument is given, then tabs are set 62.Ar tabstop 63spaces apart instead of the default 8. 64If multiple tabstops are given then the tabs are set at those 65specific columns. 66.Pp 67.Nm unexpand 68puts tabs back into the data from the standard input or the named 69files and writes the result on the standard output. 70.Pp 71Option (with 72.Nm unexpand 73only): 74.Bl -tag -width flag 75.It Fl a 76By default, only leading blanks and tabs 77are reconverted to maximal strings of tabs. 78If the 79.Fl a 80option is given, then tabs are inserted whenever they would compress the 81resultant file by replacing two or more characters. 82.El 83.Sh HISTORY 84The 85.Nm 86command appeared in 87.Bx 3.0 . 88