CRE Programmer's Guide

CRE Services
Common Run-Time Environment (CRE) Programmer’s Guide—528146-004
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Using CRE Services
Using CRE Services
Using Standard Functions
The CRE provides a library of standard functions that are required by the language-
specific run-time libraries to support your program. The CRE library functions define
the same semantics as those used in C-series run-time libraries, including the slight
variations that are defined by some of the languages.
The CRE ensures that if an error occurs, function behavior is consistent within a
language and, as much as possible, across languages.
For example, the SQRT function always uses the same rules to validate its
parameter’s domain, regardless of the language from which the SQRT function is
called.
The format of the error message that the CRE writes to standard log if the SQRT
parameter is not within the proper domain (that is, if it is less than zero) has the same
format as all other messages written to standard log.
TNS CRE library functions are intended for the use of the C, COBOL, and FORTRAN
run-time libraries, not user-written C, COBOL, or FORTRAN routines. Likewise, the
Table 2-6. TNS CRE Services Available in the OSS and Guardian Environments
Function or Function Group
OSS Environment
(G-Series Systems) Guardian Environment
CRE Standard Files No Yes
$RECEIVE Limited Yes
CRE_Terminator_ Yes Yes
Exception (Trap) Handling No Yes
Process Pairs No Yes
Signal Handling Yes No
Table 2-7. Native CRE Services Available in the OSS and Guardian
Environments
Function or Function Group OSS Environment Guardian Environment
CRE Standard Files No Yes
$RECEIVE Limited Yes
CRE_Terminator_ Yes Yes
Exception (Trap) Handling No No
Process Pairs No Yes
Signal Handling Yes Yes