xstr(1)                 (BSD Compatibility Package)                 xstr(1)

NAME
     xstr - extract strings from C programs to implement shared strings

SYNOPSIS
     /usr/ucb/xstr [-v] [-c] [-l name] [file]

DESCRIPTION
     xstr maintains a strings file into which strings in component parts of
     a large program are hashed. The strings are replaced with references
     to this common area. This serves to implement shared constant strings.

     The

          xstr -c file

     command will extract the strings from the C source in file and replace
     string references with expressions of the form (&xstr[number]). A
     declaration of xstr is prepended to the file. The resulting C source
     code is placed in the x.c file for compiling. The strings from the
     file file are placed in the strings file if they are not there
     already. Repeated strings and strings which are suffixes of existing
     strings do not initiate changes in the database.

     Once all components of a large program have been compiled, an xs.c
     file can be created with

          xstr

     which defines the common xstr array. This xs.c file should then be
     compiled and loaded with the rest of the program.

     xstr does not touch the strings file unless new items are added. make
     can therefore avoid remaking xs.o unless absolutely necessary.

     xstr can also be used on a single file. The

          xstr file

     command creates x.c and xs.c files as before, without using or touch-
     ing any strings file in the same directory.

     It may be useful to run xstr after the C preprocessor if any macro
     definitions yield strings or if there is conditional code which con-
     tains strings. xstr reads from its standard input when the "-" argu-
     ment is given instead of file. An appropriate command sequence for
     running xstr after the C preprocessor is:

          cc -E name.c | xstr -c -
          cc -c x.c
          mv x.o name.o





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xstr(1)                 (BSD Compatibility Package)                 xstr(1)

OPTIONS
     -v        (verbose) The changes to the strings file are logged to
               standard error.

     -c        Handles individual source files of a large program (similar
               to cc -c file).

     -l name   The array bears the name name in x.c and xs.c instead of
               xstr.

NOTES
     If a string is a suffix of another string in the strings file, but the
     shorter string is seen first by xstr, both strings will be placed in
     the strings file, whereas just the longer one would suffice.

FILES
     strings   Strings file

     x.c       Massaged C source

     xs.c      C source for definition of array xstr

SEE ALSO
     cc(1-ucb).






























Page 2                       Reliant UNIX 5.44                Printed 11/98