CRE Programmer's Guide

Introducing the CRE

Common Run-Time Environment (CRE) Programmer’s Guide—528146-004

1-8

Advantages of Using the CRE

In the Guardian environment, the CRE has these advantages:

•

Removes many restrictions on mixed-language programming. For example, in the

Guardian environment all routines in a program can share access to the standard

files (standard input, standard output, and standard log) and $RECEIVE, not just

those written in the same language. (In the OSS environment, the file system

supports standard files explicitly.)

•

Allows a routine to be written in the language best suited for its task. For example:

A program can have its file operations written in COBOL and its list

management in TAL or C.

A software development group might have a set of standard FORTRAN

routines that it uses to build its TAL or COBOL programs. The CRE makes

these routines available to all programs, regardless of the language.

•

Allows access to functions that are not defined as part of its own language or

run-time library. The CRE functions can be called from any language.

•

Enables you to convert applications from one programming language into another

programming language in phases. For example, suppose you need to convert an

application from TAL into C. You can divide the routines in the TAL application into

functional sets. As you convert each set of routines to C, you can test each set by

binding the TAL and C routines into one program.

•

Allows easier porting of programs to HP NonStop servers. Not only does the CRE

make it easier to port mixed-language programs, but you can rewrite performance-

critical routines in the language best suited for running on NonStop servers.

Table 1-3. Language Support in TNS CRE and native CRE

Application Language TNS CRE Native CRE

COBOL Yes (using the COBOL85 or

cobol compiler)

Yes (using the ECOBOL, ecobol,

nmcobol, or NMCOBOL compiler)

FORTRAN Yes No

CYes Yes

C++ Yes Yes

TAL Yes No

pTAL No Yes

Note. The CRE does not support mixed TNS and native programs (that is, programs that

contain both TNS object code/accelerated object code and TNS/R or TNS/E native object

code).