1.\" Copyright (c) 1980, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)xstr.1 8.2 (Berkeley) 12/30/93 33.\" $FreeBSD: src/usr.bin/xstr/xstr.1,v 1.13 2007/11/02 12:07:07 ru Exp $ 34.\" 35.Dd December 30, 1993 36.Dt XSTR 1 37.Os 38.Sh NAME 39.Nm xstr 40.Nd "extract strings from C programs to implement shared strings" 41.Sh SYNOPSIS 42.Nm 43.Op Fl cv 44.Op Fl 45.Op Ar 46.Sh DESCRIPTION 47The 48.Nm 49utility maintains a file 50.Pa strings 51into which strings in component parts of a large program are hashed. 52These strings are replaced with references to this common area. 53This serves to implement shared constant strings, most useful if they 54are also read-only. 55.Pp 56The following options are available: 57.Bl -tag -width indent 58.It Fl 59Read from the standard input. 60.It Fl c 61Extract the strings from the C source 62.Ar file 63or the standard input 64.Pq Fl , 65replacing 66string references by expressions of the form 67.Li (&xstr[number]) 68for some 69.Ar number . 70An appropriate declaration of 71.Va xstr 72is prepended to the file. 73The resulting C text is placed in the file 74.Pa x.c , 75to then be compiled. 76The strings from this file are placed in the 77.Pa strings 78data base if they are not there already. 79Repeated strings and strings which are suffixes of existing strings 80do not cause changes to the data base. 81.It Fl v 82Verbose mode. 83.El 84.Pp 85After all components of a large program have been compiled a file 86.Pa xs.c 87declaring the common 88.Va xstr 89space can be created by a command of the form 90.Pp 91.Dl xstr 92.Pp 93The file 94.Pa xs.c 95should then be compiled and loaded with the rest 96of the program. 97If possible, the array can be made read-only (shared) saving 98space and swap overhead. 99.Pp 100The 101.Nm 102utility can also be used on a single file. 103A command 104.Bd -literal -offset indent 105xstr name 106.Ed 107.Pp 108creates files 109.Pa x.c 110and 111.Pa xs.c 112as before, without using or affecting any 113.Pa strings 114file in the same directory. 115.Pp 116It may be useful to run 117.Nm 118after the C preprocessor if any macro definitions yield strings 119or if there is conditional code which contains strings 120which may not, in fact, be needed. 121An appropriate command sequence for running 122.Nm 123after the C preprocessor is: 124.Pp 125.Bd -literal -offset indent -compact 126cc -E name.c | xstr -c - 127cc -c x.c 128mv x.o name.o 129.Ed 130.Pp 131The 132.Nm 133utility does not touch the file 134.Pa strings 135unless new items are added, thus 136.Xr make 1 137can avoid remaking 138.Pa xs.o 139unless truly necessary. 140.Sh FILES 141.Bl -tag -width ".Pa /tmp/xs*" -compact 142.It Pa strings 143data base of strings 144.It Pa x.c 145massaged C source 146.It Pa xs.c 147C source for definition of array 148.Va xstr 149.It Pa /tmp/xs* 150temporary file when 151.Dq Li "xstr name" 152does not touch 153.Pa strings 154.El 155.Sh SEE ALSO 156.Xr mkstr 1 157.Sh HISTORY 158The 159.Nm 160command appeared in 161.Bx 3.0 . 162.Sh BUGS 163If a string is a suffix of another string in the data base, 164but the shorter string is seen first by 165.Nm 166both strings will be placed in the data base, when just 167placing the longer one there will do. 168