gtpa2m3t | Application Programming |
It should be assumed that all application programs will require modification at some point. Ease of understanding and modification is therefore of primary importance. Programs should be designed and coded so that external changes such as system configuration and values or other program changes have the least possible impact. The key to this is to keep coding symbolic. Absolute values should be avoided; use length attributes and calculations from symbolic references. All assembler programs and TARGET(TPF) functions are limited to 4KB and ISO-C functions have no size limit in main storage. Assembly language and TARGET(TPF) programs should leave room for expansion (perhaps 20% of record size) when they are originally coded.