CRE Programmer's Guide

CRE Services

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

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Using CRE Functions to Access the Standard Files

Except under unusual circumstances, use only high-level language constructs to

access standard files. For programs running in the CRE, each language-specific run-

time library calls CRE functions to process your requests. Under some circumstances,

however, you might need to invoke CRE functions or system procedures directly. For

example, you might invoke CRE_File_Control_ to issue a page eject command to a

printer. If your program invokes CRE functions or system procedures directly, you must

ensure that the routines and procedures you invoke do not alter or interfere with the I/O

state maintained by the CRE.

The CRE provides the following functions for standard files. The functions are

described in Section 6, CRE Service Functions.

Figure 2-9. Using the CRE—The C Routine Writes to the File $VOL.SUBVOL.FILE

CRE_File_Close_ CRE_File_Open_ CRE_Hometerm_Open_

CRE_File_Control_ CRE_File_Output_ CRE_Log_Message_

CRE_File_Input_ CRE_File_Retrycheck_ CRE_Spool_Start_

CRE_File_Message_ CRE_File_Setmode_

COBOL:

TAL:

C: printf(“C\n”);

C Run-Time Library

210VST .VSD

$VOL

SUBVOL.FILE

COBOL Run-Time Library

NonStop Operating System

Common Run-Time Environment Library

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