.\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)expand.1 8.1 (Berkeley) 6/9/93 .\" $FreeBSD: src/usr.bin/expand/expand.1,v 1.15 2006/10/13 16:22:24 ru Exp $ .\" .Dd October 13, 2006 .Dt EXPAND 1 .Os .Sh NAME .Nm expand , .Nm unexpand .Nd expand tabs to spaces, and vice versa .Sh SYNOPSIS .Nm .Oo .Fl t .Sm off .Ar tab1 , tab2 , ... , tabn .Sm on .Oc .Op Ar .Nm unexpand .Oo .Fl a | t .Sm off .Ar tab1 , tab2 , ... , tabn .Sm on .Oc .Op Ar .Sh DESCRIPTION The .Nm utility processes the named files or the standard input writing the standard output with tabs changed into blanks. Backspace characters are preserved into the output and decrement the column count for tab calculations. The .Nm utility is useful for pre-processing character files (before sorting, looking at specific columns, etc.) that contain tabs. .Pp The .Nm unexpand utility puts tabs back into the data from the standard input or the named files and writes the result on the standard output. .Pp The following options are available: .Bl -tag -width indent .It Fl a .Nm ( unexpand only.) By default, only leading blanks and tabs are reconverted to maximal strings of tabs. If the .Fl a option is given, then tabs are inserted whenever they would compress the resultant file by replacing two or more characters. .It Fl t Sm Ar tab1 , tab2 , ... , tabn Sm Set tab stops at column positions .Ar tab1 , tab2 , ... , tabn . If only a single number is given, tab stops are set that number of column positions apart instead of the default number of 8. .El .Sh ENVIRONMENT The .Ev LANG , LC_ALL and .Ev LC_CTYPE environment variables affect the execution of .Nm and .Nm unexpand as described in .Xr environ 7 . .Sh EXIT STATUS .Ex -std expand unexpand .Sh STANDARDS The .Nm and .Nm unexpand utilities conform to .St -p1003.1-2001 . .Sh HISTORY The .Nm command appeared in .Bx 3.0 .