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