PCRE2\_SUBSTRING\_LENGTH\_BYNUMBER(3) Library Functions Manual PCRE2\_SUBSTRING\_LENGTH\_BYNUMBER(3)

# [NAME](#NAME)

PCRE2 - Perl-compatible regular expressions (revised API)

# [SYNOPSIS](#SYNOPSIS)

**#include <pcre2.h>**

```
int pcre2_substring_length_bynumber(pcre2_match_data *match_data,
  uint32_t number, PCRE2_SIZE *length);
```

# [DESCRIPTION](#DESCRIPTION)

This function returns the length of a matched substring, identified by number. The arguments are:

*match\_data* The match data block for the match  
*number* The substring number  
*length* Where to return the length, or NULL

The third argument may be NULL if all you want to know is whether or not a substring is set. The yield is zero on success, or a negative error code otherwise. After a partial match, only substring 0 is available.

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.

22 December 2014 PCRE2 10.49

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Document: pcre2_substring_length_bynumber(3) from pcre2 10.49-r2 (Chainguard OS)
Source: https://github.com/PCRE2Project/pcre2.git