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If you build PCRE with a locale setting that is not the standard C locale, the
character tables may be different (see next paragraph). In some cases, this may
cause failures in the second set of tests. For example, in a locale where the
isprint() function yields TRUE for characters in the range 128-255, the use of
[:isascii:] inside a character class defines a different set of characters, and
this shows up in this test as a difference in the compiled code, which is being
listed for checking. Where the comparison test output contains [\x00-\x7f] the
test will contain [\x00-\xff], and similarly in some other cases. This is not a
bug in PCRE.

The third set of tests checks pcre_maketables(), the facility for building a
set of character tables for a specific locale and using them instead of the
default tables. The tests make use of the "fr_FR" (French) locale. Before
running the test, the script checks for the presence of this locale by running
the "locale" command. If that command fails, or if it doesn't include "fr_FR"
in the list of available locales, the third test cannot be run, and a comment
is output to say why. If running this test produces instances of the error

  ** Failed to set locale "fr_FR"

in the comparison output, it means that locale is not available on your system,
despite being listed by "locale". This does not mean that PCRE is broken.

[If you are trying to run this test on Windows, you may be able to get it to
work by changing "fr_FR" to "french" everywhere it occurs. Alternatively, use
RunTest.bat. The version of RunTest.bat included with PCRE 7.4 and above uses
Windows versions of test 2. More info on using RunTest.bat is included in the
document entitled NON-UNIX-USE.]

The fourth test checks the UTF-8 support. It is not run automatically unless
PCRE is built with UTF-8 support. To do this you must set --enable-utf8 when
running "configure". This file can be also fed directly to the perltest script,
provided you are running Perl 5.8 or higher. (For Perl 5.6, a small patch,
commented in the script, can be be used.)

The fifth test checks error handling with UTF-8 encoding, and internal UTF-8
features of PCRE that are not relevant to Perl.

The sixth test checks the support for Unicode character properties. It it not
run automatically unless PCRE is built with Unicode property support. To to
this you must set --enable-unicode-properties when running "configure".

The seventh, eighth, and ninth tests check the pcre_dfa_exec() alternative
matching function, in non-UTF-8 mode, UTF-8 mode, and UTF-8 mode with Unicode
property support, respectively. The eighth and ninth tests are not run
automatically unless PCRE is build with the relevant support.


Character tables
----------------

For speed, PCRE uses four tables for manipulating and identifying characters
whose code point values are less than 256. The final argument of the
pcre_compile() function is a pointer to a block of memory containing the
concatenated tables. A call to pcre_maketables() can be used to generate a set
of tables in the current locale. If the final argument for pcre_compile() is
passed as NULL, a set of default tables that is built into the binary is used.

The source file called pcre_chartables.c contains the default set of tables. By
default, this is created as a copy of pcre_chartables.c.dist, which contains
tables for ASCII coding. However, if --enable-rebuild-chartables is specified
for ./configure, a different version of pcre_chartables.c is built by the
program dftables (compiled from dftables.c), which uses the ANSI C character
handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
build the table sources. This means that the default C locale which is set for
your system will control the contents of these default tables. You can change
the default tables by editing pcre_chartables.c and then re-building PCRE. If
you do this, you should take care to ensure that the file does not get
automatically re-generated. The best way to do this is to move
pcre_chartables.c.dist out of the way and replace it with your customized
tables.

When the dftables program is run as a result of --enable-rebuild-chartables,
it uses the default C locale that is set on your system. It does not pay
attention to the LC_xxx environment variables. In other words, it uses the
system's default locale rather than whatever the compiling user happens to have
set. If you really do want to build a source set of character tables in a
locale that is specified by the LC_xxx variables, you can run the dftables
program by hand with the -L option. For example:

  ./dftables -L pcre_chartables.c.special

The first two 256-byte tables provide lower casing and case flipping functions,
respectively. The next table consists of three 32-byte bit maps which identify
digits, "word" characters, and white space, respectively. These are used when
building 32-byte bit maps that represent character classes for code points less
than 256.

The final 256-byte table has bits indicating various character types, as
follows:

    1   white space character
    2   letter
    4   decimal digit
    8   hexadecimal digit
   16   alphanumeric or '_'
  128   regular expression metacharacter or binary zero

You should not alter the set of characters that contain the 128 bit, as that
will cause PCRE to malfunction.


File manifest
-------------

The distribution should contain the following files:

(A) Source files of the PCRE library functions and their headers:

  dftables.c              auxiliary program for building pcre_chartables.c
                            when --enable-rebuild-chartables is specified

  pcre_chartables.c.dist  a default set of character tables that assume ASCII
                            coding; used, unless --enable-rebuild-chartables is
                            specified, by copying to pcre_chartables.c

  pcreposix.c             )
  pcre_compile.c          )
  pcre_config.c           )
  pcre_dfa_exec.c         )
  pcre_exec.c             )
  pcre_fullinfo.c         )
  pcre_get.c              ) sources for the functions in the library,
  pcre_globals.c          )   and some internal functions that they use
  pcre_info.c             )
  pcre_maketables.c       )
  pcre_newline.c          )
  pcre_ord2utf8.c         )
  pcre_refcount.c         )
  pcre_study.c            )
  pcre_tables.c           )
  pcre_try_flipped.c      )
  pcre_ucp_searchfuncs.c  )
  pcre_valid_utf8.c       )
  pcre_version.c          )
  pcre_xclass.c           )
  pcre_printint.src       ) debugging function that is #included in pcretest,
                          )   and can also be #included in pcre_compile()
  pcre.h.in               template for pcre.h when built by "configure"
  pcreposix.h             header for the external POSIX wrapper API
  pcre_internal.h         header for internal use
  ucp.h                   ) headers concerned with
  ucpinternal.h           )   Unicode property handling
  ucptable.h              ) (this one is the data table)

  config.h.in             template for config.h, which is built by "configure"

  pcrecpp.h               public header file for the C++ wrapper
  pcrecpparg.h.in         template for another C++ header file
  pcre_scanner.h          public header file for C++ scanner functions
  pcrecpp.cc              )
  pcre_scanner.cc         ) source for the C++ wrapper library

  pcre_stringpiece.h.in   template for pcre_stringpiece.h, the header for the
                            C++ stringpiece functions
  pcre_stringpiece.cc     source for the C++ stringpiece functions

(B) Source files for programs that use PCRE:

  pcredemo.c              simple demonstration of coding calls to PCRE
  pcregrep.c              source of a grep utility that uses PCRE
  pcretest.c              comprehensive test program

(C) Auxiliary files:

  132html                 script to turn "man" pages into HTML
  AUTHORS                 information about the author of PCRE
  ChangeLog               log of changes to the code
  CleanTxt                script to clean nroff output for txt man pages
  Detrail                 script to remove trailing spaces
  HACKING                 some notes about the internals of PCRE
  INSTALL                 generic installation instructions
  LICENCE                 conditions for the use of PCRE
  COPYING                 the same, using GNU's standard name
  Makefile.in             ) template for Unix Makefile, which is built by
                          )   "configure"
  Makefile.am             ) the automake input that was used to create
                          )   Makefile.in
  NEWS                    important changes in this release
  NON-UNIX-USE            notes on building PCRE on non-Unix systems
  PrepareRelease          script to make preparations for "make dist"
  README                  this file
  RunTest                 a Unix shell script for running tests
  RunGrepTest             a Unix shell script for pcregrep tests
  aclocal.m4              m4 macros (generated by "aclocal")
  config.guess            ) files used by libtool,
  config.sub              )   used only when building a shared library
  configure               a configuring shell script (built by autoconf)
  configure.ac            ) the autoconf input that was used to build
                          )   "configure" and config.h
  depcomp                 ) script to find program dependencies, generated by
                          )   automake
  doc/*.3                 man page sources for the PCRE functions
  doc/*.1                 man page sources for pcregrep and pcretest
  doc/index.html.src      the base HTML page
  doc/html/*              HTML documentation
  doc/pcre.txt            plain text version of the man pages
  doc/pcretest.txt        plain text documentation of test program
  doc/perltest.txt        plain text documentation of Perl test program
  install-sh              a shell script for installing files
  libpcre.pc.in           template for libpcre.pc for pkg-config
  libpcrecpp.pc.in        template for libpcrecpp.pc for pkg-config
  ltmain.sh               file used to build a libtool script
  missing                 ) common stub for a few missing GNU programs while
                          )   installing, generated by automake
  mkinstalldirs           script for making install directories
  perltest.pl             Perl test program
  pcre-config.in          source of script which retains PCRE information
  pcrecpp_unittest.cc          )
  pcre_scanner_unittest.cc     ) test programs for the C++ wrapper
  pcre_stringpiece_unittest.cc )
  testdata/testinput*     test data for main library tests
  testdata/testoutput*    expected test results
  testdata/grep*          input and output for pcregrep tests

(D) Auxiliary files for cmake support

  CMakeLists.txt
  config-cmake.h.in

(E) Auxiliary files for VPASCAL

  makevp.bat
  makevp_c.txt
  makevp_l.txt
  pcregexp.pas

(F) Auxiliary files for building PCRE "by hand"

  pcre.h.generic          ) a version of the public PCRE header file
                          )   for use in non-"configure" environments
  config.h.generic        ) a version of config.h for use in non-"configure"
                          )   environments

(F) Miscellaneous

  RunTest.bat            a script for running tests under Windows

Philip Hazel
Email local part: ph10
Email domain: cam.ac.uk
Last updated: 21 September 2007