Page alignment can be important to performance. If your program is created with options STGMDL(*SNGLVL) and DTAMDL(*P128) [these are the defaults and they instruct the compiler to build a program that allocates its working storage from single-level storage and uses 16-byte pointers], you must calculate an increment and add it to the pointer. For example, to round a pointer up to the next page boundary, you can try something like this: #include <mih/lspco.h> /* _LSPCO -- load space origin */ #define NEXT_PAGE(p) ( (char *)_LSPCO(p) \ + (((p - (char*)_LSPCO(p)) + (PAGESIZE-1)) & (~(PAGESIZE-1))) ) The page size is 4096 on current AS/400 and iSeries models, but it can also be materialized with the MATRMD MI instruction. If your program is created with options TERASPACE(*YES) STGMDL(*TERASPACE) DTAMDL(*LLP64) [these instruct the compiler to build a program that allocates its working storage from Teraspace and uses 8-byte pointers], you can effectively treat the pointer like an integer, although pointers are the same size as "long long" integers. To round an 8-byte pointer up to the next page boundary, you can try something like this: #define NEXT_PAGE(p) \ (char*)( (long long)( (char*)p + (PAGESIZE-1) ) & (~(PAGESIZE-1)) ) "Terrence Enger" <tenger@xxxxxxxxxxxxxxxx> wrote in message news:188.8.131.52.20030901191529.00ce4c50@xxxxxxxxxxxxxx > If so, is there a portable type which defines an integer at least large > enough to hold an address? Can I cast an integer expression to a pointer, > or do I have to calculate an increment and add it to the pointer?