Интерактивная система просмотра системных руководств (man-ов)
xstr (1)
xstr (1) ( Solaris man: Команды и прикладные программы пользовательского уровня )
>> xstr (1) ( FreeBSD man: Команды и прикладные программы пользовательского уровня )
BSD mandoc
NAME
xstr
- extract strings from C programs to implement shared strings
SYNOPSIS
[-cv
]
[-
]
[file ...
]
DESCRIPTION
The
utility maintains a file
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.
The following options are available:
-
Read from the standard input.
-c
Extract the strings from the C source
file
or the standard input
(-
)
replacing
string references by expressions of the form
(&xstr[number])
for some
number
An appropriate declaration of
xstr
is prepended to the file.
The resulting C text is placed in the file
x.c
to then be compiled.
The strings from this file are placed in the
strings
data base if they are not there already.
Repeated strings and strings which are suffixes of existing strings
do not cause changes to the data base.
-v
Verbose mode.
After all components of a large program have been compiled a file
xs.c
declaring the common
xstr
space can be created by a command of the form
xstr
The file
xs.c
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.
The
utility can also be used on a single file.
A command
xstr name
creates files
x.c
and
xs.c
as before, without using or affecting any
strings
file in the same directory.
It may be useful to run
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.
An appropriate command sequence for running
after the C preprocessor is:
cc -E name.c | xstr -c -
cc -c x.c
mv x.o name.o
The
utility does not touch the file
strings
unless new items are added, thus
make(1)
can avoid remaking
xs.o
unless truly necessary.
FILES
strings
data base of strings
x.c
massaged C source
xs.c
C source for definition of array
xstr
/tmp/xs*
temporary file when
``xstr name
''
does not touch
strings
If a string is a suffix of another string in the data base,
but the shorter string is seen first by
both strings will be placed in the data base, when just
placing the longer one there will do.
