PCRE2\_PATTERN\_INFO(3) Library Functions Manual PCRE2\_PATTERN\_INFO(3)

# [NAME](#NAME)

PCRE2 - Perl-compatible regular expressions (revised API)

# [SYNOPSIS](#SYNOPSIS)

**#include <pcre2.h>**

```
int pcre2_pattern_info(const pcre2_code *code, uint32_t what,
   void *where);
```

# [DESCRIPTION](#DESCRIPTION)

This function returns information about a compiled pattern. Its arguments are:

*code* Pointer to a compiled regular expression pattern  
*what* What information is required  
*where* Where to put the information

The recognized values for the *what* argument, and the information they request are as follows:

PCRE2\_INFO\_ALLOPTIONS Final options after compiling  
PCRE2\_INFO\_ARGOPTIONS Options passed to **pcre2\_compile()**  
PCRE2\_INFO\_BACKREFMAX Number of highest backreference  
PCRE2\_INFO\_BSR What \\R matches:  
PCRE2\_BSR\_UNICODE: Unicode line endings  
PCRE2\_BSR\_ANYCRLF: CR, LF, or CRLF only  
PCRE2\_INFO\_CAPTURECOUNT Number of capturing subpatterns  
PCRE2\_INFO\_DEPTHLIMIT Backtracking depth limit if set,  
otherwise PCRE2\_ERROR\_UNSET  
PCRE2\_INFO\_EXTRAOPTIONS Extra options that were passed in the  
compile context  
PCRE2\_INFO\_FIRSTBITMAP Bitmap of first code units, or NULL  
PCRE2\_INFO\_FIRSTCODETYPE Type of start-of-match information  
0 nothing set  
1 first code unit is set  
2 start of string or after newline  
PCRE2\_INFO\_FIRSTCODEUNIT First code unit when type is 1  
PCRE2\_INFO\_FRAMESIZE Size of backtracking frame  
PCRE2\_INFO\_HASBACKSLASHC Return 1 if pattern contains \\C  
PCRE2\_INFO\_HASCRORLF Return 1 if explicit CR or LF matches  
exist in the pattern  
PCRE2\_INFO\_HEAPLIMIT Heap memory limit if set,  
otherwise PCRE2\_ERROR\_UNSET  
PCRE2\_INFO\_JCHANGED Return 1 if (?J) or (?-J) was used  
PCRE2\_INFO\_JITSIZE Size of JIT compiled code, or 0  
PCRE2\_INFO\_LASTCODETYPE Type of must-be-present information  
0 nothing set  
1 code unit is set  
PCRE2\_INFO\_LASTCODEUNIT Last code unit when type is 1  
PCRE2\_INFO\_MATCHEMPTY 1 if the pattern can match an  
empty string, 0 otherwise  
PCRE2\_INFO\_MATCHLIMIT Match limit if set,  
otherwise PCRE2\_ERROR\_UNSET  
PCRE2\_INFO\_MAXLOOKBEHIND Length (in characters) of the longest  
lookbehind assertion  
PCRE2\_INFO\_MINLENGTH Lower bound length of matching strings  
PCRE2\_INFO\_NAMECOUNT Number of named subpatterns  
PCRE2\_INFO\_NAMEENTRYSIZE Size of name table entries  
PCRE2\_INFO\_NAMETABLE Pointer to name table  
PCRE2\_CONFIG\_NEWLINE Code for the newline sequence:  
PCRE2\_NEWLINE\_CR  
PCRE2\_NEWLINE\_LF  
PCRE2\_NEWLINE\_CRLF  
PCRE2\_NEWLINE\_ANY  
PCRE2\_NEWLINE\_ANYCRLF  
PCRE2\_NEWLINE\_NUL  
PCRE2\_INFO\_RECURSIONLIMIT Obsolete synonym for PCRE2\_INFO\_DEPTHLIMIT  
PCRE2\_INFO\_SIZE Size of compiled pattern

If *where* is NULL, the function returns the amount of memory needed for the requested information, in bytes. Otherwise, the *where* argument must point to an unsigned 32-bit integer (uint32\_t variable), except for the following *what* values, when it must point to a variable of the type shown:

PCRE2\_INFO\_FIRSTBITMAP const uint8\_t *  
PCRE2\_INFO\_JITSIZE size\_t  
PCRE2\_INFO\_NAMETABLE PCRE2\_SPTR  
PCRE2\_INFO\_SIZE size\_t

The yield of the function is zero on success or:

PCRE2\_ERROR\_NULL the argument *code* is NULL  
PCRE2\_ERROR\_BADMAGIC the "magic number" was not found  
PCRE2\_ERROR\_BADOPTION the value of *what* is invalid  
PCRE2\_ERROR\_BADMODE the pattern was compiled in the wrong mode  
PCRE2\_ERROR\_UNSET the requested information is not set

There is a complete description of the PCRE2 native API in the **pcre2api** page and a description of the POSIX API in the **pcre2posix** page.

14 February 2019 PCRE2 10.49

---

Document: pcre2_pattern_info(3) from pcre2 10.49-r2 (Chainguard OS)
Source: https://github.com/PCRE2Project/pcre2.git