Hi Thomas, Depends on the operating system. For example, on Amiga OS, the "get 50 bytes of memory from the OS" call is... size_t size = 50; int memtype = MEMF_PUBLIC | MEMF_CLEAR; void* ptr = AllocMem(size, memtype), ...and the "release memory back to the OS" is... FreeMem(ptr, size) Usually C malloc/free (and C++ new/delete) under the covers allocates a larger extent from the OS, and manage that C memory heap (or C++ global store) itself. The SAS/C++ 6.56 compiler provides a lot of low level heap management functions, but most compilers do not expose their heap management mechanisms. For Unix (Linux, Solaris, Darwin), you may want to refer to the man pages for mmap, brk, sbrk, malloc, lf64, getrlimit, mprotect, munmap, lockf, mlockall, msync, plock, sysconf, fnctl and shmat. For Win32... *shrug* HTH, --Eljay
