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HPFOPEN

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Edition 7 E0701 ♥
Edition 7 E0300
Edition 6 E0195

NM callable only.

Creates file objects and supports FIFO files.

Syntax



           I32      I32      I32V     *
  HPFOPEN (filenum, status [,itemnum, item] [...]);


NOTE: Up to 41 itemnum/item pairs can be specified.

Parameters


filenum

32-bit signed integer by reference (required)

Returns a file descriptor for a FIFO file.

Can be used safely with all file system intrinsics that require a 16-bit file number to be passed in the intrinsic call (for example, FREAD, FWRITE, FCLOSE).

status

32-bit signed integer by reference (optional)

Returns the status of the HPFOPEN call. If no errors or warnings are encountered, status returns 32-bits of zero. If errors or warnings are encountered, status is interpreted as two 16-bit fields:

Bits (0:16) comprise status.info. A negative value indicates an error condition, and a positive value indicates a warning condition. Refer to the MPE/iX Error Message Manual Volumes 1, 2 and 3 for a description of its value.

Bits (16:16) comprise.status.subsys. The value represents the subsystem that set the status information. The subsystem identifier for HPFOPEN is 143.


CAUTION: If an error or warning is encountered and the status parameter was not specified, HPFOPEN causes the calling process to abort.

itemnum

32-bit signed integer by value (optional)

Passes the item number.


NOTE: An itemnum takes precedence over any previously specified duplicate itemnum. Any duplicated itemnum is flagged as a warning.

item

type varies by reference (optional)

Passes and/or returns the option indicated by the corresponding itemnum parameter.


HPFOPEN Itemnum/Item Values

Operation Notes


Enables creation of a new file on a shareable device and defines the physical characteristics of that file prior to access. Enables access to existing files. Returns a file number to the calling process that uniquely identifies the file. Use the file number to reference the file in calls to other intrinsics.

Related Information


Intrinsics FCLOSE, FOPEN, FRENAME, HPFDUPLICATE, HPPIPE
Manuals Accessing Files Programmer's Guide
Using KSAM XL
KSAM/3000 Reference Manual




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