PCRE2\_JIT\_STACK\_ASSIGN(3) Library Functions Manual PCRE2\_JIT\_STACK\_ASSIGN(3)

# [NAME](#NAME)

PCRE2 - Perl-compatible regular expressions (revised API)

# [SYNOPSIS](#SYNOPSIS)

**#include <pcre2.h>**

```
void pcre2_jit_stack_assign(pcre2_match_context *mcontext,
  pcre2_jit_callback callback_function, void *callback_data);
```

# [DESCRIPTION](#DESCRIPTION)

This function provides control over the memory used by JIT as a run-time stack when **pcre2\_match()** or **pcre2\_jit\_match()** is called with a pattern that has been successfully processed by the JIT compiler. The information that determines which stack is used is put into a match context that is subsequently passed to a matching function. The arguments of this function are:

mcontext a pointer to a match context  
callback a callback function  
callback\_data a JIT stack or a value to be passed to the callback

If *mcontext* is NULL, the function returns immediately, without doing anything.

If *callback* is NULL and *callback\_data* is NULL, an internal 32KiB block on the machine stack is used.

If *callback* is NULL and *callback\_data* is not NULL, *callback\_data* must be a valid JIT stack, the result of calling **pcre2\_jit\_stack\_create()**.

If *callback* not NULL, it is called with *callback\_data* as an argument at the start of matching, in order to set up a JIT stack. If the result is NULL, the internal 32KiB stack is used; otherwise the return value must be a valid JIT stack, the result of calling **pcre2\_jit\_stack\_create()**.

You may safely use the same JIT stack for multiple patterns, as long as they are all matched in the same thread. In a multithread application, each thread must use its own JIT stack. For more details, see the **pcre2jit** page.

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.

13 August 2018 PCRE2 10.49

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Document: pcre2_jit_stack_assign(3) from pcre2 10.49-r2 (Chainguard OS)
Source: https://github.com/PCRE2Project/pcre2.git