[unix-history] / man / xstr.u

.TH XSTR UCB 2/24/79 UCB
.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 approporiate 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(UCB)
.SH AUTHOR
Bill Joy
.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
1aa6c056 BJ	1	.TH XSTR UCB 2/24/79 UCB
	2	.SH NAME
	3	xstr \- extract strings from C programs to implement shared strings
	4	.SH SYNOPSIS
	5	.B xstr
	6	[
	7	.B \-c
	8	] [
	9	.B \-
	10	] [
	11	file
	12	]
	13	.SH DESCRIPTION
	14	.I Xstr
	15	maintains a file
	16	.I strings
	17	into which strings in component parts of a large program are hashed.
	18	These strings are replaced with references to this common area.
	19	This serves to implement shared constant strings, most useful if they
	20	are also read-only.
	21	.PP
	22	The command
	23	.PP
	24	.DT
	25	\fBxstr \-c\fR name
	26	.PP
	27	will extract the strings from the C source in name, replacing
	28	string references by expressions of the form (&xstr[number])
	29	for some number.
	30	An approporiate declaration of
	31	.I xstr
	32	is prepended to the file.
	33	The resulting C text is placed in the file
	34	.I x.c,
	35	to then be compiled.
	36	The strings from this file are placed in the
	37	.I strings
	38	data base if they are not there already.
	39	Repeated strings and strings which are suffices of existing strings
	40	do not cause changes to the data base.
	41	.PP
	42	After all components of a large program have been compiled a file
	43	.I xs.c
	44	declaring the common
	45	.I xstr
	46	space can be created by a command of the form
	47	.PP
	48	.DT
	49	\fBxstr\fR
	50	.PP
	51	This
	52	.I xs.c
	53	file should then be compiled and loaded with the rest
	54	of the program.
	55	If possible, the array can be made read-only (shared) saving
	56	space and swap overhead.
	57	.PP
	58	.I Xstr
	59	can also be used on a single file.
	60	A command
	61	.PP
	62	.DT
	63	\fBxstr\fR name
	64	.PP
65	creates files
66	.I x.c
67	and
68	.I xs.c
69	as before, without using or affecting any
70	.I strings
71	file in the same directory.
72	.PP
73	It may be useful to run
74	.I xstr
75	after the C preprocessor if any macro definitions yield strings
76	or if there is conditional code which contains strings
77	which may not, in fact, be needed.
78	.I Xstr
79	reads from its standard input when the argument `\-' is given.
80	An appropriate command sequence for running
81	.I xstr
82	after the C preprocessor is:
83	.PP
84	.nf
85	.DT
86	\fBcc \-E\fR name.c \| \fBxstr \-c\fR \-
87	\fBcc \-c\fR x.c
88	\fBmv\fR x.o name.o
89	.fi
90	.PP
91	.I Xstr
92	does not touch the file
93	.I strings
94	unless new items are added, thus
95	.I make
96	can avoid remaking
97	.I xs.o
98	unless truly necessary.
99	.SH FILES
100	.DT
101	strings Data base of strings
102	.br
103	x.c Massaged C source
104	.br
105	xs.c C source for definition of array `xstr'
106	.br
107	/tmp/xs* Temp file when `xstr name' doesn't touch
108	.I strings
109	.SH "SEE ALSO"
110	mkstr(UCB)
111	.SH AUTHOR
112	Bill Joy
113	.SH BUGS
114	If a string is a suffix of another string in the data base,
115	but the shorter string is seen first by
116	.I xstr
117	both strings will be placed in the data base, when just
118	placing the longer one there will do.