"Fossies" - the Fresh Open Source Software Archive

Member "pcre-8.42/doc/pcre_dfa_exec.3" (31 Jan 2014, 5317 Bytes) of package /linux/misc/pcre-8.42.tar.bz2:


Caution: As a special service "Fossies" has tried to format the requested manual source page into HTML format but links to other man pages may be missing or even errorneous. Alternatively you can here view or download the uninterpreted manual source code. A member file download can also be achieved by clicking within a package contents listing on the according byte size field.

PCRE_DFA_EXEC

NAME
SYNOPSIS
DESCRIPTION

NAME

PCRE - Perl-compatible regular expressions

SYNOPSIS

#include <pcre.h>

int pcre_dfa_exec(const pcre *code, const pcre_extra *extra,
const char *
subject, int length, int startoffset,
int
options, int *ovector, int ovecsize,
int *
workspace, int wscount);

int pcre16_dfa_exec(const pcre16 *code, const pcre16_extra *extra,
PCRE_SPTR16
subject, int length, int startoffset,
int
options, int *ovector, int ovecsize,
int *
workspace, int wscount);

int pcre32_dfa_exec(const pcre32 *code, const pcre32_extra *extra,
PCRE_SPTR32
subject, int length, int startoffset,
int
options, int *ovector, int ovecsize,
int *
workspace, int wscount);

DESCRIPTION

This function matches a compiled regular expression against a given subject string, using an alternative matching algorithm that scans the subject string just once (not Perl-compatible). Note that the main, Perl-compatible, matching function is pcre[16|32]_exec(). The arguments for this function are:

code Points to the compiled pattern
extra
Points to an associated pcre[16|32]_extra structure,
or is NULL
subject
Points to the subject string
length
Length of the subject string
startoffset
Offset in the subject at which to start matching
options
Option bits
ovector
Points to a vector of ints for result offsets
ovecsize
Number of elements in the vector
workspace
Points to a vector of ints used as working space
wscount
Number of elements in the vector

The units for length and startoffset are bytes for pcre_exec(), 16-bit data items for pcre16_exec(), and 32-bit items for pcre32_exec(). The options are:

PCRE_ANCHORED Match only at the first position
PCRE_BSR_ANYCRLF \R matches only CR, LF, or CRLF
PCRE_BSR_UNICODE \R matches all Unicode line endings
PCRE_NEWLINE_ANY Recognize any Unicode newline sequence
PCRE_NEWLINE_ANYCRLF Recognize CR, LF, & CRLF as newline sequences
PCRE_NEWLINE_CR Recognize CR as the only newline sequence
PCRE_NEWLINE_CRLF Recognize CRLF as the only newline sequence
PCRE_NEWLINE_LF Recognize LF as the only newline sequence
PCRE_NOTBOL Subject is not the beginning of a line
PCRE_NOTEOL Subject is not the end of a line
PCRE_NOTEMPTY An empty string is not a valid match
PCRE_NOTEMPTY_ATSTART An empty string at the start of the subject
is not a valid match
PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
PCRE_NO_UTF16_CHECK Do not check the subject for UTF-16
validity (only relevant if PCRE_UTF16
was set at compile time)
PCRE_NO_UTF32_CHECK Do not check the subject for UTF-32
validity (only relevant if PCRE_UTF32
was set at compile time)
PCRE_NO_UTF8_CHECK Do not check the subject for UTF-8
validity (only relevant if PCRE_UTF8
was set at compile time)
PCRE_PARTIAL ) Return PCRE_ERROR_PARTIAL for a partial
PCRE_PARTIAL_SOFT ) match if no full matches are found
PCRE_PARTIAL_HARD Return PCRE_ERROR_PARTIAL for a partial match
even if there is a full match as well
PCRE_DFA_SHORTEST Return only the shortest match
PCRE_DFA_RESTART Restart after a partial match

There are restrictions on what may appear in a pattern when using this matching function. Details are given in the pcrematching documentation. For details of partial matching, see the pcrepartial page.

A pcre[16|32]_extra structure contains the following fields:

flags Bits indicating which fields are set
study_data
Opaque data from pcre[16|32]_study()
match_limit
Limit on internal resource use
match_limit_recursion
Limit on internal recursion depth
callout_data
Opaque data passed back to callouts
tables
Points to character tables or is NULL
mark
For passing back a *MARK pointer
executable_jit
Opaque data from JIT compilation

The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT, PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA, PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT. For this matching function, the match_limit and match_limit_recursion fields are not used, and must not be set. The PCRE_EXTRA_EXECUTABLE_JIT flag and the corresponding variable are ignored.

There is a complete description of the PCRE native API in the pcreapi page and a description of the POSIX API in the pcreposix page.