--- code/trunk/README 2007/02/24 21:38:49 27 +++ code/trunk/README 2007/02/24 21:39:17 41 @@ -1,76 +1,87 @@ -README file for PCRE (Perl-compatible regular expressions) ----------------------------------------------------------- +README file for PCRE (Perl-compatible regular expression library) +----------------------------------------------------------------- -******************************************************************************* -* IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00 * -* * -* Please note that there has been a change in the API such that a larger * -* ovector is required at matching time, to provide some additional workspace. * -* The new man page has details. This change was necessary in order to support * -* some of the new functionality in Perl 5.005. * -* * -* IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00 * -* * -* Another (I hope this is the last!) change has been made to the API for the * -* pcre_compile() function. An additional argument has been added to make it * -* possible to pass over a pointer to character tables built in the current * -* locale by pcre_maketables(). To use the default tables, this new arguement * -* should be passed as NULL. * -******************************************************************************* +Please read the NEWS file if you are upgrading from a previous release. -The distribution should contain the following files: - ChangeLog log of changes to the code - Makefile for building PCRE - README this file - RunTest a shell script for running tests - Tech.Notes notes on the encoding - pcre.3 man page for the functions - pcreposix.3 man page for the POSIX wrapper API - dftables.c auxiliary program for building chartables.c - maketables.c ) - study.c ) source of - pcre.c ) the functions - pcreposix.c ) - pcre.h header for the external API - pcreposix.h header for the external POSIX wrapper API - internal.h header for internal use - pcretest.c test program - pgrep.1 man page for pgrep - pgrep.c source of a grep utility that uses PCRE - perltest Perl test program - testinput test data, compatible with Perl 5.004 and 5.005 - testinput2 test data for error messages and non-Perl things - testinput3 test data, compatible with Perl 5.005 - testinput4 test data for locale-specific tests - testoutput test results corresponding to testinput - testoutput2 test results corresponding to testinput2 - testoutput3 test results corresponding to testinput3 - testoutput4 test results corresponding to testinput4 - -To build PCRE, edit Makefile for your system (it is a fairly simple make file, -and there are some comments at the top) and then run it. It builds two -libraries called libpcre.a and libpcreposix.a, a test program called pcretest, -and the pgrep command. - -To test PCRE, run the RunTest script in the pcre directory. This runs pcretest -on each of the testinput files in turn, and compares the output with the -contents of the corresponding testoutput file. A file called testtry is used to -hold the output from pcretest (which is documented below). +Building PCRE on a Unix system +------------------------------ + +To build PCRE on a Unix system, run the "configure" command in the PCRE +distribution directory. This is a standard GNU "autoconf" configuration script, +for which generic instructions are supplied in INSTALL. On many systems just +running "./configure" is sufficient, but the usual methods of changing standard +defaults are available. For example + +CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local + +specifies that the C compiler should be run with the flags '-O2 -Wall' instead +of the default, and that "make install" should install PCRE under /opt/local +instead of the default /usr/local. The "configure" script builds two files: + +. Makefile is built by copying Makefile.in and making certain substitutions. +. config.h is built by copying config.in and making certain substitutions. + +Once "configure" has run, you can run "make". It builds two libraries called +libpcre.a and libpcreposix.a, a test program called pcretest, and the pgrep +command. You can use "make install" to copy these, and the public header file +pcre.h, to appropriate live directories on your system, in the normal way. + + +Shared libraries on Unix systems +-------------------------------- + +The default distribution builds static libraries. It is also possible to build +PCRE as two shared libraries. This support is new and experimental and may not +work on all systems. It relies on the "libtool" scripts - these are distributed +with PCRE. To build PCRE using shared libraries you must use --enable-shared +when configuring it. For example + +./configure --prefix=/usr/gnu --enable-shared + +Then run "make" in the usual way. It should build a "libtool" script and use +this to compile and link shared libraries, which are placed in a subdirectory +called .libs. The programs pcretest and pgrep are built to use these +uninstalled libraries by means of wrapper scripts. When you use "make install" +to install shared libraries, pgrep is automatically re-built to use the newly +installed library before it itself is installed. -To run pcretest on just one of the test files, give its number as an argument -to RunTest, for example: + +Building on non-Unix systems +---------------------------- + +For a non-Unix system, read the comments in the file NON-UNIX-USE. 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, because it uses only +Standard C functions. + + +Testing PCRE +------------ + +To test PCRE on a Unix system, run the RunTest script in the pcre directory. +(This can also be run by "make runtest" or "make check".) For other systems, +see the instruction in NON-UNIX-USE. + +The script runs the pcretest test program (which is documented in +doc/pcretest.txt) on each of the testinput files (in the testdata directory) in +turn, and compares the output with the contents of the corresponding testoutput +file. A file called testtry is used to hold the output from pcretest. To run +pcretest on just one of the test files, give its number as an argument to +RunTest, for example: RunTest 3 The first and third test files can also be fed directly into the perltest -program to check that Perl gives the same results. The third file requires the +script to check that Perl gives the same results. The third file requires the additional features of release 5.005, which is why it is kept separate from the main test input, which needs only Perl 5.004. In the long run, when 5.005 is widespread, these two test files may get amalgamated. -The second set of tests check pcre_info(), pcre_study(), error detection and -run-time flags that are specific to PCRE, as well as the POSIX wrapper API. +The second set of tests check 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. The fourth 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 @@ -85,15 +96,6 @@ 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. -To install PCRE, copy libpcre.a to any suitable library directory (e.g. -/usr/local/lib), pcre.h to any suitable include directory (e.g. -/usr/local/include), and pcre.3 to any suitable man directory (e.g. -/usr/local/man/man3). - -To install the pgrep command, copy it to any suitable binary directory, (e.g. -/usr/local/bin) and pgrep.1 to any suitable man directory (e.g. -/usr/local/man/man1). - PCRE has its own native API, but a set of "wrapper" functions that are based on the POSIX API are also supplied in the library libpcreposix.a. Note that this just provides a POSIX calling interface to PCRE: the regular expressions @@ -109,19 +111,20 @@ PCRE uses four tables for manipulating and identifying characters. 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() is used to -generate a set of tables in the current locale. However, if the final argument -is passed as NULL, a set of default tables that is built into the binary is -used. +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 set your system will control the -contents of the 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. +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 @@ -142,153 +145,71 @@ will cause PCRE to malfunction. -The pcretest program --------------------- +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 + get.c ) + maketables.c ) + study.c ) source of + pcre.c ) the functions + pcreposix.c ) + pcre.h header for the external API + pcreposix.h header for the external POSIX wrapper API + internal.h header for internal use + config.in template for config.h, which is built by configure + +(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 + 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 a Unix shell script for running tests + config.guess ) files used by libtool, + config.sub ) used only when building a shared library + configure a configuring shell script (built by autoconf) + configure.in the autoconf input used to build configure + doc/Tech.Notes notes on the encoding + doc/pcre.3 man page source for the PCRE functions + doc/pcre.html HTML version + doc/pcre.txt plain text version + doc/pcreposix.3 man page source for the POSIX wrapper API + doc/pcreposix.html HTML version + doc/pcreposix.txt plain text version + doc/pcretest.txt documentation of test program + doc/perltest.txt documentation of Perl test program + doc/pgrep.1 man page source for the pgrep utility + doc/pgrep.html HTML version + doc/pgrep.txt plain text version + install-sh a shell script for installing files + ltconfig ) files used to build "libtool", + ltmain.sh ) used only when building a shared library + pcretest.c test program + perltest Perl test program + pgrep.c source of a grep utility that uses PCRE + testdata/testinput1 test data, compatible with Perl 5.004 and 5.005 + testdata/testinput2 test data for error messages and non-Perl things + testdata/testinput3 test data, compatible with Perl 5.005 + testdata/testinput4 test data for locale-specific tests + testdata/testoutput1 test results corresponding to testinput1 + testdata/testoutput2 test results corresponding to testinput2 + testdata/testoutput3 test results corresponding to testinput3 + testdata/testoutput4 test results corresponding to testinput4 -This program is intended for testing PCRE, but it can also be used for -experimenting with regular expressions. +(C) Auxiliary files for Win32 DLL -If it is given two filename arguments, it reads from the first and writes to -the second. If it is given only one filename argument, it reads from that file -and writes to stdout. Otherwise, it reads from stdin and writes to stdout, and -prompts for each line of input. - -The program handles any number of sets of input on a single input file. Each -set starts with a regular expression, and continues with any number of data -lines to be matched against the pattern. An empty line signals the end of the -set. The regular expressions are given enclosed in any non-alphameric -delimiters, for example - - /(a|bc)x+yz/ - -and may be followed by i, m, s, or x to set the PCRE_CASELESS, PCRE_MULTILINE, -PCRE_DOTALL, or PCRE_EXTENDED options, respectively. These options have the -same effect as they do in Perl. - -There are also some upper case options that do not match Perl options: /A, /E, -and /X set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, and PCRE_EXTRA respectively. - -The /L option must be followed directly by the name of a locale, for example, - - /pattern/Lfr - -For this reason, it must be the last option letter. The given locale is set, -pcre_maketables() is called to build a set of character tables for the locale, -and this is then passed to pcre_compile() when compiling the regular -expression. Without an /L option, NULL is passed as the tables pointer; that -is, /L applies only to the expression on which it appears. - -The /I option requests that pcretest output information about the compiled -expression (whether it is anchored, has a fixed first character, and so on). It -does this by calling pcre_info() after compiling an expression, and outputting -the information it gets back. If the pattern is studied, the results of that -are also output. - -The /D option is a PCRE debugging feature, which also assumes /I. It causes the -internal form of compiled regular expressions to be output after compilation. - -The /S option causes pcre_study() to be called after the expression has been -compiled, and the results used when the expression is matched. - -Finally, the /P option causes pcretest to call PCRE via the POSIX wrapper API -rather than its native API. When this is done, all other options except /i and -/m are ignored. REG_ICASE is set if /i is present, and REG_NEWLINE is set if /m -is present. The wrapper functions force PCRE_DOLLAR_ENDONLY always, and -PCRE_DOTALL unless REG_NEWLINE is set. - -A regular expression can extend over several lines of input; the newlines are -included in it. See the testinput files for many examples. - -Before each data line is passed to pcre_exec(), leading and trailing whitespace -is removed, and it is then scanned for \ escapes. The following are recognized: - - \a alarm (= BEL) - \b backspace - \e escape - \f formfeed - \n newline - \r carriage return - \t tab - \v vertical tab - \nnn octal character (up to 3 octal digits) - \xhh hexadecimal character (up to 2 hex digits) - - \A pass the PCRE_ANCHORED option to pcre_exec() - \B pass the PCRE_NOTBOL option to pcre_exec() - \Odd set the size of the output vector passed to pcre_exec() to dd - (any number of decimal digits) - \Z pass the PCRE_NOTEOL option to pcre_exec() - -A backslash followed by anything else just escapes the anything else. If the -very last character is a backslash, it is ignored. This gives a way of passing -an empty line as data, since a real empty line terminates the data input. - -If /P was present on the regex, causing the POSIX wrapper API to be used, only -\B, and \Z have any effect, causing REG_NOTBOL and REG_NOTEOL to be passed to -regexec() respectively. - -When a match succeeds, pcretest outputs the list of identified substrings that -pcre_exec() returns, starting with number 0 for the string that matched the -whole pattern. Here is an example of an interactive pcretest run. - - $ pcretest - Testing Perl-Compatible Regular Expressions - PCRE version 0.90 08-Sep-1997 - - re> /^abc(\d+)/ - data> abc123 - 0: abc123 - 1: 123 - data> xyz - No match - -Note that while patterns can be continued over several lines (a plain ">" -prompt is used for continuations), data lines may not. However newlines can be -included in data by means of the \n escape. - -If the -p option is given to pcretest, it is equivalent to adding /P to each -regular expression: the POSIX wrapper API is used to call PCRE. None of the -following flags has any effect in this case. - -If the option -d is given to pcretest, it is equivalent to adding /D to each -regular expression: the internal form is output after compilation. - -If the option -i is given to pcretest, it is equivalent to adding /I to each -regular expression: information about the compiled pattern is given after -compilation. - -If the option -s is given to pcretest, it outputs the size of each compiled -pattern after it has been compiled. - -If the -t option is given, each compile, study, and match is run 10000 times -while being timed, and the resulting time per compile or match is output in -milliseconds. Do not set -t with -s, because you will then get the size output -10000 times and the timing will be distorted. If you want to change the number -of repetitions used for timing, edit the definition of LOOPREPEAT at the top of -pcretest.c - - - -The perltest program --------------------- - -The perltest program tests Perl's regular expressions; it has the same -specification as pcretest, and so can be given identical input, except that -input patterns can be followed only by Perl's lower case options. The contents -of testinput and testinput3 meet this condition. - -The data lines are processed as Perl strings, so if they contain $ or @ -characters, these have to be escaped. For this reason, all such characters in -the testinput file are escaped so that it can be used for perltest as well as -for pcretest, and the special upper case options such as /A that pcretest -recognizes are not used in this file. The output should be identical, apart -from the initial identifying banner. - -The testinput2 and testinput4 files are not suitable for feeding to Perltest, -since they do make use of the special upper case options and escapes that -pcretest uses to test some features of PCRE. The first of these files also -contains malformed regular expressions, in order to check that PCRE diagnoses -them correctly. + dll.mk + pcre.def Philip Hazel -January 1999 +January 2000