[unix-history] / usr / src / usr.bin / xstr / xstr.1

.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)xstr.1	6.2 (Berkeley) %G%
.\"
.TH XSTR 1 ""
.UC
.SH NAME
xstr \- extract strings from C programs to implement shared strings
.SH SYNOPSIS
.B xstr
[
.B \-c
] [
.B \-
] [
file
]
.SH DESCRIPTION
.I Xstr
maintains a file
.I strings
into which strings in component parts of a large program are hashed.
These strings are replaced with references to this common area.
This serves to implement shared constant strings, most useful if they
are also read-only.
.PP
The command
.PP
.DT
	\fBxstr \-c\fR name
.PP
will extract the strings from the C source in name, replacing
string references by expressions of the form (&xstr[number])
for some number.
An appropriate declaration of
.I xstr
is prepended to the file.
The resulting C text is placed in the file
.I x.c,
to then be compiled.
The strings from this file are placed in the
.I strings
data base if they are not there already.
Repeated strings and strings which are suffices of existing strings
do not cause changes to the data base.
.PP
After all components of a large program have been compiled a file
.I xs.c
declaring the common
.I xstr
space can be created by a command of the form
.PP
.DT
	\fBxstr\fR
.PP
This
.I xs.c
file should then be compiled and loaded with the rest
of the program.
If possible, the array can be made read-only (shared) saving
space and swap overhead.
.PP
.I Xstr
can also be used on a single file.
A command
.PP
.DT
	\fBxstr\fR name
.PP
creates files
.I x.c
and
.I xs.c
as before, without using or affecting any
.I strings
file in the same directory.
.PP
It may be useful to run
.I xstr
after the C preprocessor if any macro definitions yield strings
or if there is conditional code which contains strings
which may not, in fact, be needed.
.I Xstr
reads from its standard input when the argument `\-' is given.
An appropriate command sequence for running
.I xstr
after the C preprocessor is:
.PP
.nf
.DT
	\fBcc \-E\fR name.c | \fBxstr \-c\fR \-
	\fBcc \-c\fR x.c
	\fBmv\fR x.o name.o
.fi
.PP
.I Xstr
does not touch the file
.I strings
unless new items are added, thus
.I make
can avoid remaking
.I xs.o
unless truly necessary.
.SH FILES
.DT
strings		Data base of strings
.br
x.c		Massaged C source
.br
xs.c		C source for definition of array `xstr'
.br
/tmp/xs*	Temp file when `xstr name' doesn't touch
.I strings
.SH "SEE ALSO"
mkstr(1)
.SH BUGS
If a string is a suffix of another string in the data base,
but the shorter string is seen first by
.I xstr
both strings will be placed in the data base, when just
placing the longer one there will do.
Commit	Line	Data
b74e1486 KM	1	.\" Copyright (c) 1980 Regents of the University of California.
	2	.\" All rights reserved. The Berkeley software License Agreement
	3	.\" specifies the terms and conditions for redistribution.
	4	.\"
c004a4b5	5	.\" @(#)xstr.1 6.2 (Berkeley) %G%
b74e1486	6	.\"
4baabe9a	7	.TH XSTR 1 ""
b74e1486 KM	8	.UC
	9	.SH NAME
	10	xstr \- extract strings from C programs to implement shared strings
	11	.SH SYNOPSIS
	12	.B xstr
	13	[
	14	.B \-c
	15	] [
	16	.B \-
	17	] [
	18	file
	19	]
	20	.SH DESCRIPTION
	21	.I Xstr
	22	maintains a file
	23	.I strings
	24	into which strings in component parts of a large program are hashed.
	25	These strings are replaced with references to this common area.
	26	This serves to implement shared constant strings, most useful if they
	27	are also read-only.
	28	.PP
	29	The command
	30	.PP
	31	.DT
	32	\fBxstr \-c\fR name
	33	.PP
	34	will extract the strings from the C source in name, replacing
	35	string references by expressions of the form (&xstr[number])
	36	for some number.
	37	An appropriate declaration of
	38	.I xstr
	39	is prepended to the file.
	40	The resulting C text is placed in the file
	41	.I x.c,
	42	to then be compiled.
	43	The strings from this file are placed in the
	44	.I strings
	45	data base if they are not there already.
	46	Repeated strings and strings which are suffices of existing strings
	47	do not cause changes to the data base.
	48	.PP
	49	After all components of a large program have been compiled a file
	50	.I xs.c
	51	declaring the common
	52	.I xstr
	53	space can be created by a command of the form
	54	.PP
	55	.DT
	56	\fBxstr\fR
	57	.PP
	58	This
	59	.I xs.c
	60	file should then be compiled and loaded with the rest
	61	of the program.
	62	If possible, the array can be made read-only (shared) saving
	63	space and swap overhead.
	64	.PP
	65	.I Xstr
	66	can also be used on a single file.
	67	A command
	68	.PP
	69	.DT
	70	\fBxstr\fR name
	71	.PP
72	creates files
73	.I x.c
74	and
75	.I xs.c
76	as before, without using or affecting any
77	.I strings
78	file in the same directory.
79	.PP
80	It may be useful to run
81	.I xstr
82	after the C preprocessor if any macro definitions yield strings
83	or if there is conditional code which contains strings
84	which may not, in fact, be needed.
85	.I Xstr
86	reads from its standard input when the argument `\-' is given.
87	An appropriate command sequence for running
88	.I xstr
89	after the C preprocessor is:
90	.PP
91	.nf
92	.DT
93	\fBcc \-E\fR name.c \| \fBxstr \-c\fR \-
94	\fBcc \-c\fR x.c
95	\fBmv\fR x.o name.o
96	.fi
97	.PP
98	.I Xstr
99	does not touch the file
100	.I strings
101	unless new items are added, thus
102	.I make
103	can avoid remaking
104	.I xs.o
105	unless truly necessary.
106	.SH FILES
107	.DT
108	strings Data base of strings
109	.br
110	x.c Massaged C source
111	.br
112	xs.c C source for definition of array `xstr'
113	.br
114	/tmp/xs* Temp file when `xstr name' doesn't touch
115	.I strings
116	.SH "SEE ALSO"
117	mkstr(1)
b74e1486 KM	118	.SH BUGS
	119	If a string is a suffix of another string in the data base,
	120	but the shorter string is seen first by
	121	.I xstr
	122	both strings will be placed in the data base, when just
	123	placing the longer one there will do.