Q40589: The Definition of Reentrancy

Article: Q40589
Product(s): See article
Version(s): 4.00 5.00 5.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | re-entrant reentrant | mspl13_c
Last Modified: 16-MAY-1989

Question:

What is reentrancy?

Response:

Reentrancy is the ability of code to be executed simultaneously by
more than one process. It requires that the code not change the state
of any global object, such as global variables or hardware. Any code
compiled by the C compiler that uses only automatic variables will be
reentrant only if the library functions used by the code are also
reentrant.

Note: Most library routines are not reentrant, nor is DOS or BIOS.