diff options
Diffstat (limited to 'lib/libc/stdlib/malloc.3')
-rw-r--r-- | lib/libc/stdlib/malloc.3 | 37 |
1 files changed, 17 insertions, 20 deletions
diff --git a/lib/libc/stdlib/malloc.3 b/lib/libc/stdlib/malloc.3 index b191415..94a3fd6 100644 --- a/lib/libc/stdlib/malloc.3 +++ b/lib/libc/stdlib/malloc.3 @@ -111,25 +111,6 @@ is zero and is not a null pointer, the object it points to is freed. .Pp -.Pp -The default is to compile with the ``SANITY'' option, -which trades a couple of percent of performance for rather rigorous -sanity checking of the arguments passed to -.Xr free -and -.Xr realloc . -.Pp -If compiled without the ``SANITY'' option and the argument does not -match a pointer earlier returned by the -.Xr calloc , -.Xr malloc , -or -.Xr realloc -function, or if the space has been deallocated by a call to -.Fn free -or -.Xr realloc , -general havoc will be imminent. .Sh ENVIRONMENT This malloc will check the environment for a variable called .Em MALLOC_OPTIONS @@ -139,15 +120,31 @@ Flags are single letters, uppercase means on, lowercase means off. .It A ``abort'' malloc will coredump the process, rather that tollerate failure. This is a very handy debugging aid, since the core file will represent the -time of failure, rather than when the NULL pointer was accessed. +time of failure, +rather than when the NULL pointer was accessed. + .It D ``dump'' malloc will dump statistics in a file called ``malloc.out'' at exit. + +.It J +``junk'' fill some junk into the area allocated. +Currently junk is bytes of 0xd0, this is pronounced ``Duh'' :-) + .It R ``realloc'' always reallocate when .Fn realloc is called, even if the initial allocation was big enough. This can substantially aid in compacting memory. + +.It Z +``zero'' fill some junk into the area allocated (see ``J''), +except for the exact length the user asked for, which is zerod. + .El +.Pp +The ``J'' and ``Z'' is mostly for testing and debugging, +if a program changes behaviour if either of these options are used, +it is buggy. .Sh RETURN VALUES The .Fn malloc |