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     The malloc family of functions allocates a memory block of at
     least <size> bytes. The block may be larger than <size> bytes
     because of space required for alignment and for maintenance
     information. If size is 0, malloc allocates a zero-length item
     in the heap and returns a valid pointer to that item.
 
     The storage space pointed to by the return value is guaranteed to
     be suitably aligned for storage of any type of object. To get a
     pointer to a type other than void, use a type cast on the return
     value.
 
     In large data models (compact, large, and huge), malloc maps to
     _fmalloc. In small data models (tiny, small, and medium), malloc
     maps to _nmalloc.
 
     The _fmalloc function allocates a memory block of at least <size>
     bytes outside the default data segment. The _fmalloc function
     returns a far pointer to void. If a block of more than 64K is
     needed, use the halloc function.
 
     The _bmalloc function allocates a memory block of at least <size>
     bytes in the based heap specified by the segment selector <seg>.
 
     The various malloc functions allocate memory in the heap specified
     in the list below:
 
     Function     Heap Segment
 
     malloc       Depends on data model of program
     _bmalloc     Based heap specified by seg value
     _fmalloc     Far heap (outside default data segment)
     _nmalloc     Near heap (inside default data segment)
 
     If you are creating programs to run in both real mode and
     protected mode, you should probably bind with APILMR.OBJ as well
     as API.LIB and OS2.LIB. This is necessary in any case in which a
     program will use the _nmalloc function.
 
     The functions that call the malloc family of routines are listed
     below. In addition, the C start-up code uses malloc to allocate
     storage for the environ/envp[] and argv[] strings and arrays.
 
     The following C run-time routines call _nmalloc:
 
          _nrealloc()     _ncalloc()     _nstrdup()
 
     The following C run-time routines call _fmalloc:
 
          _frealloc()     _fcalloc()     _fstrdup()
 
     The following routines call malloc:
 
          calloc()       fseek()         scanf()
          execl()        fsetpos()       _searchenv()
          execle()       _fullpath()     setvbuf()
          execlp()       fwrite()        spawnl()
          execlpe()      getc()          spawnle()
          execv()        getchar()       spawnlp()
          execve()       getcwd()        spawnlpe()
          execvp()       _getdcwd()      spawnv()
          execvpe()      gets()          spawnve()
          fgetc()        getw()          spawnvp()
          fgetchar()     _popen()        spawnvpe()
          fgets()        printf()        strdup()
          fprintf()      putc()          system()
          fputc()        putchar()       tempnam()
          fputchar()     putenv()        ungetc()
          fputs()        puts()          vfprintf()
          fread()        putw()          vprintf()
          fscanf()       realloc()
 
     The following routines call malloc only in the multithread
     run-time libraries (LLIBCMT, LLIBCDLL, CDLLOBJS), but not in the
     regular run-time libraries:
 
          asctime()        localtime()     _strerror()
          _beginthread     mktime()        tmpfile()
          ctime()          strerror()      tmpnam()
          gmtime()
 
     In Microsoft Quick C version 2.0, the _fmalloc function would
     retry allocating within the default data segment if sufficient
     memory was not available outside the default data segment.
     As noted above, version 2.5 returns NULL under these conditions.
 
     In version 2.0, the start-up code used malloc only if wild-card
     expansion was used.
 
     The _freect(), _memavl(), and _memmax() functions called malloc in
     version 2.0 but do not do so in version 2.5.
 
     Return Value
 
     The malloc function returns a void pointer to the allocated space.
     The _nmalloc function returns a ( void _near * ) and _fmalloc
     returns a ( void _far * ). The _bmalloc function returns a
     ( void _based( void ) * ).
 
     The _malloc, _fmalloc and _nmalloc functions return NULL if there
     is insufficient memory available. The _bmalloc function returns
     _NULLOFF if there is insufficient memory available.
 
     Always check the return from the malloc function, even if the
     amount of memory requested is small.
                                    -♦-