re entrant programs

[kurup]

Hi everyone,

Does anyone know what are reentrant programs. If u know some site from where i can get more information please let me know that.......

thank you,

kurup

 

[Dimandja]

Hi kurup,

Reentrant programs are functions/modules that do not hold static data between calls.

For example, given an online system, program Client calls program Server. For Server to be reentrant (it normally should be), Server must be coded not to 'remember' any data between calls. All data to be processed must be kept and passed in the call by program Client.

A reentrant program is one that can execute in multiple copies (threads) simultaneously. Each copy, of course, servicing a different request.

Dimandja

 

[senthiljith]

hi kurup,

a point to add up.
Reentrant program is a must to attain MultiThreading Environment. Under CICS command level COBOL application programs, quasi-reentrancy (reentrancy is called quasi-reentrancy under CICS) is automatically ensured



senthiljith

 

[gregsimpson]

A clear way to think of it is as follows.

Each run of the reentrant program has a unique copy of working storage.

Each run of the reentrant program uses the same procedure division, the logic path followed only altering due to the particular working storage applied.

Greg