Table of Contents
This is part of Win16 API which allow to create versions of program from one source code to run under OS/2 and Win16. Under OS/2 program can be running under Win-OS/2 if program is Windows NE executable, and with help on Windows Libraries for OS/2, if it is OS/2 NE executable. Here is a WLO to OS/2 API mapping draft
LocalAlloc
Brief
Allocates a block of memory from the local heap of the current data segment.
Syntax
HLOCAL WINAPI LocalAlloc( UINT uFlags, UINT uBytes );
Parameters
- uFlags – Allocation attributes. Common flags:
- LMEM_FIXED (0x0000) – Allocates fixed memory; the return value is a pointer.
- LMEM_MOVEABLE (0x0002) – Allocates movable memory; returns a handle.
- LMEM_ZEROINIT (0x0040) – Initializes the memory to zero.
- LMEM_DISCARDABLE (0x0F00) – Makes the block discardable (only with LMEM_MOVEABLE).
- LMEM_NOCOMPACT (0x0010) – Prevents heap compaction for this allocation.
- LMEM_NODISCARD (0x0020) – Prevents discarding of other blocks.
Shorthands: LHND (LMEM_MOVEABLE | LMEM_ZEROINIT), LPTR (LMEM_FIXED | LMEM_ZEROINIT).
- uBytes – Number of bytes to allocate. If zero and LMEM_MOVEABLE is set, returns a handle to a discarded object.
Return Value
If successful, returns a handle to the allocated object. For LMEM_FIXED, this handle is actually a pointer.
Returns NULL on failure. Call GetLastError for extended error information.
Notes
- For movable blocks, use LocalLock to obtain a pointer before accessing the memory.
- The internal lock count of a new block is zero.
Example Code
C Binding
HLOCAL hMem = LocalAlloc(LMEM_MOVEABLE | LMEM_ZEROINIT, 1024); HLOCAL hMem2 = LocalAlloc(LHND, 1024);
MASM Binding
push 0042h ; LMEM_MOVEABLE | LMEM_ZEROINIT push 0400h ; 1024 bytes call LocalAlloc
See also
| Group | Functions |
|---|---|
| Module manager | GETVERSION GETMODULEHANDLE GETMODULEUSAGE GETMODULEFILENAME GETPROCADDRESS MAKEPROCINSTANCE FREEPROCINSTANCE GETINSTANCEDATA CATCH THROW GETCODEHANDLE LOADLIBRARY |
| Memory Manager | GlobalAlloc GlobalCompact GlobalDiscard GlobalFree GlobalLock GlobalReAlloc GlobalSize GlobalUnlock GlobalFlags LocalInit LocalAlloc LocalCompact LocalDiscard LocalFree LocalLock LocalFreeze LocalMelt LocalReAlloc LocalSize LocalUnlock LocalHandleDelta LockData UnlockData LocalFlags |
| Task Scheduler | GetCurrentTask Yield SetPriority |
| Resource Manager | AddFontResource RemoveFontResource LoadBitmap LoadCursor LoadIcon LoadMenu LoadString LoadAccelerators FindResource LoadResource AllocResource LockResource FreeResource AccessResource SizeofResource SetResourceHandler |
| String Translation | AnsiUpper AnsiLower AnsiNext AnsiPrev |
| Atom Manager | InitAtomTable AddAtom DeleteAtom FindAtom GetAtomName |
| Windows Initialization File | GetProfileInt GetProfileString WriteProfileString |
| Debugging | FatalExit |
| File I/O | _lopen _lcreat _llseek _lread _lwrite _lclose OpenFile GetTempFileName GetTempDrive |
| Registry | RegOpenKey RegCreateKey RegCloseKey RegDeleteKey RegSetValue RegQueryValue RegEnumKey |