MALLINFO(3) NEWLIB MALLINFO(3)NAME
2.24 `mallinfo', `malloc_stats', `mallopt'--malloc support
SYNOPSIS
#include <malloc.h>
struct mallinfomallinfo(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 releas‐
ing 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 pad‐
ding to allocate whenever `_sbrk_r' is called to allocate more space.
The alternate functions `_mallinfo_r', `_malloc_stats_r', and `_mal‐
lopt_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 dif‐
ferent parameters on different systems. `malloc_stats' is not porta‐
ble.
SEE ALSOmallinfo is part of the library. The full documentation for is main‐
tained as a Texinfo manual. If info and are properly installed at your
site, the command
info
will give you access to the complete manual.
NEWLIB April 2010 MALLINFO(3)