TAL Reference Manual

Introduction
TAL Reference Manual—526371-001
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CRE Services
CRE Services
The CRE provides services that support mixed-language programs compiled on D-
series compilers. A mixed-language program can consist of C, COBOL85,FORTRAN,
Pascal, and TAL routines.
A routine is a program unit that is callable from anywhere in your program. The term
routine can represent:
•
A C function
•
A COBOL85 program
•
A FORTRAN program or subprogram
•
A Pascal procedure or function
•
A TAL procedure or function procedure
When you use the CRE, each routine in your program, regardless of language, can:
•
Use the routine’s run-time library without overwriting the data of another run-time
library
•
Share data in the CRE user heap
•
Share access to the standard files—standard input, standard output, and standard
log
•
Call math and string functions provided in the CRELIB file
•
Call Saved Messages Utility (SMU) functions provided in the Common Language
Utility Library (CLULIB file)
Without the CRE, only routines written in the language of the MAIN routine can fully
access their run-time library. For example, if the MAIN routine is written in TAL, a
routine written in another language might not be able to use its own run-time library.
For more information on CRE guidelines for TAL programs, see Section 17, “Mixed-
Language Programming”. The CRE Programmer’s Guide describes the services
provided by the CRE, including the math, string, and SMU functions.