Manpage of MALLINFO

MALLINFO

Section: NEWLIB (3)
Updated: 2005 Feb 23
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NAME

1.23 `mallinfo', `malloc_stats', `mallopt'-malloc support

SYNOPSIS

     #include <malloc.h>
     struct mallinfo mallinfo(void);
     void malloc_stats(void);
     int mallopt(int PARAMETER, VALUE);

     struct mallinfo _mallinfo_r(void *REENT);
     void _malloc_stats_r(void *REENT);
     int _mallopt_r(void *REENT, int PARAMETER, VALUE);

DESCRIPTION

`mallinfo' returns a structure describing the current state of memory allocation. The structure is defined in malloc.h. The following fields are defined: `arena' is the total amount of space in the heap; `ordblks' is the number of chunks which are not in use; `uordblks' is the total amount of space allocated by `malloc'; `fordblks' is the total amount of space not in use; `keepcost' is the size of the top most memory block.

`malloc_stats' print some statistics about memory allocation on standard error.

`mallopt' takes a parameter and a value. The parameters are defined in malloc.h, and may be one of the following: `M_TRIM_THRESHOLD' sets the maximum amount of unused space in the top most block before releasing it back to the system in `free' (the space is released by calling `_sbrk_r' with a negative argument); `M_TOP_PAD' is the amount of padding to allocate whenever `_sbrk_r' is called to allocate more space.

The alternate functions `_mallinfo_r', `_malloc_stats_r', and `_mallopt_r' are reentrant versions. The extra argument REENT is a pointer to a reentrancy structure.

RETURNS

`mallinfo' returns a mallinfo structure. The structure is defined in malloc.h.

`malloc_stats' does not return a result.

`mallopt' returns zero if the parameter could not be set, or non-zero if it could be set.

PORTABILITY

`mallinfo' and `mallopt' are provided by SVR4, but `mallopt' takes different parameters on different systems. `malloc_stats' is not portable.

This document was created by man2html, using the manual pages.
Time: 21:25:24 GMT, May 16, 2005