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php-4.4.7学习linux时下载的源代码

build only shared libraries.


Cross-compiling on a Unix-like system
-------------------------------------

You can specify CC and CFLAGS in the normal way to the "configure" command, in
order to cross-compile PCRE for some other host. However, during the building
process, the dftables.c source file is compiled *and run* on the local host, in
order to generate the default character tables (the chartables.c file). It
therefore needs to be compiled with the local compiler, not the cross compiler.
You can do this by specifying CC_FOR_BUILD (and if necessary CFLAGS_FOR_BUILD;
there are also CXX_FOR_BUILD and CXXFLAGS_FOR_BUILD for the C++ wrapper)
when calling the "configure" command. If they are not specified, they default
to the values of CC and CFLAGS.


Using HP's ANSI C++ compiler (aCC)
----------------------------------

Unless C++ support is disabled by specifying the "--disable-cpp" option of the
"configure" script, you *must* include the "-AA" option in the CXXFLAGS
environment variable in order for the C++ components to compile correctly.

Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
needed libraries fail to get included when specifying the "-AA" compiler
option. If you experience unresolved symbols when linking the C++ programs,
use the workaround of specifying the following environment variable prior to
running the "configure" script:

  CXXLDFLAGS="-lstd_v2 -lCsup_v2"


Building on non-Unix systems
----------------------------

For a non-Unix system, read the comments in the file NON-UNIX-USE, though if
the system supports the use of "configure" and "make" you may be able to build
PCRE in the same way as for Unix systems.

PCRE has been compiled on Windows systems and on Macintoshes, but I don't know
the details because I don't use those systems. It should be straightforward to
build PCRE on any system that has a Standard C compiler and library, because it
uses only Standard C functions.


Testing PCRE
------------

To test PCRE on a Unix system, run the RunTest script that is created by the
configuring process. There is also a script called RunGrepTest that tests the
options of the pcregrep command. If the C++ wrapper library is build, three
test programs called pcrecpp_unittest, pcre_scanner_unittest, and
pcre_stringpiece_unittest are provided.

Both the scripts and all the program tests are run if you obey "make runtest",
"make check", or "make test". For other systems, see the instructions in
NON-UNIX-USE.

The RunTest script runs the pcretest test program (which is documented in its
own man page) on each of the testinput files (in the testdata directory) in
turn, and compares the output with the contents of the corresponding testoutput
files. A file called testtry is used to hold the main output from pcretest
(testsavedregex is also used as a working file). To run pcretest on just one of
the test files, give its number as an argument to RunTest, for example:

  RunTest 2

The first test file can also be fed directly into the perltest script to check
that Perl gives the same results. The only difference you should see is in the
first few lines, where the Perl version is given instead of the PCRE version.

The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(),
pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
detection, and run-time flags that are specific to PCRE, as well as the POSIX
wrapper API. It also uses the debugging flag to check some of the internals of
pcre_compile().

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.

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 and 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
----------------

PCRE uses four tables for manipulating and identifying characters whose 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 chartables.c contains the default set of tables. This is
not supplied in the distribution, but 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 chartables.c and then re-building PCRE. If you do this, you should
probably also edit Makefile to ensure that the file doesn't ever get
re-generated.

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.

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.


Manifest
--------

The distribution should contain the following files:

(A) The actual source files of the PCRE library functions and their
    headers:

  dftables.c            auxiliary program for building 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         )
  ucptable.c            )

  pcre_printint.src     ) debugging function that is #included in pcretest, and
                        )   can also be #included in pcre_compile()

  pcre.h                the public PCRE header file
  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
  config.in             template for config.h, which is built by configure

  pcrecpp.h             the header file for the C++ wrapper
  pcrecpparg.h.in       "source" for another C++ header file
  pcrecpp.cc            )
  pcre_scanner.cc       ) source for the C++ wrapper library

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

(B) Auxiliary files:

  AUTHORS               information about the author of PCRE
  ChangeLog             log of changes to the code
  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
  NEWS                  important changes in this release
  NON-UNIX-USE          notes on building PCRE on non-Unix systems
  README                this file
  RunTest.in            template for a Unix shell script for running tests
  RunGrepTest.in        template for a Unix shell script for pcregrep tests
  config.guess          ) files used by libtool,
  config.sub            )   used only when building a shared library
  config.h.in           "source" for the config.h header file
  configure             a configuring shell script (built by autoconf)
  configure.ac          the autoconf input used to build configure
  doc/Tech.Notes        notes on the encoding
  doc/*.3               man page sources for the PCRE functions
  doc/*.1               man page sources for pcregrep and pcretest
  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         "source" for libpcre.pc for pkg-config
  ltmain.sh             file used to build a libtool script
  mkinstalldirs         script for making install directories
  pcretest.c            comprehensive test program
  pcredemo.c            simple demonstration of coding calls to PCRE
  perltest              Perl test program
  pcregrep.c            source of a grep utility that uses PCRE
  pcre-config.in        source of script which retains PCRE information
  pcrecpp_unittest.c           )
  pcre_scanner_unittest.c      ) test programs for the C++ wrapper
  pcre_stringpiece_unittest.c  )
  testdata/testinput*   test data for main library tests
  testdata/testoutput*  expected test results
  testdata/grep*        input and output for pcregrep tests

(C) Auxiliary files for Win32 DLL

  libpcre.def
  libpcreposix.def

(D) Auxiliary file for VPASCAL

  makevp.bat

Philip Hazel
Email local part: ph10
Email domain: cam.ac.uk
November 2006