DosQHandType

This call determines whether a handle references a file or a device.

This is the legacy function. It is recommended to use: "DosQueryHType".

Syntax

DosQHandType (FileHandle, HandType, FlagWord)

Parameters

FileHandle (HFILE) - input

File handle.

HandType (PUSHORT) - output

Address of the value indicating the handle type. HandType is composed of two bytes:

15 - Network bit:

0 = The handle refers to a local file, device, or pipe.

1 = Means that the handle refers to a remote file, device, or pipe.

14-8 - Reserved.

7-0 - HandleClass describes the handle class. It may take on the following values in the low byte of HandleType:

0 - Handle is for a disk file

1 - Handle is for a character device

2 - Handle is for a pipe.

Values greater than 2 are reserved.

FlagWord (PUSHORT) - output: Address of the device driver's attribute word if HandleType indicates a local character device.

Return Code

rc (USHORT) - return

Return code descriptions are:

0 NO_ERROR
6 ERROR_INVALID_HANDLE

Remarks

This function allows programs that are interactive or file-oriented to determine the source of their input. For example, CMD.EXE suppresses writing prompts if the input is from a disk file.

Example Code

C Binding

#define INCL_DOSFILEMGR

USHORT  rc = DosQHandType(FileHandle, HandType, FlagWord);

HFILE            FileHandle;    /* File handle */
PUSHORT          HandType;      /* Handle type (returned) */
PUSHORT          FlagWord;      /* Device driver attribute (returned) */

USHORT           rc;            /* return code */

MASM Binding

EXTRN  DosQHandType:FAR
INCL_DOSFILEMGR     EQU 1

PUSH   WORD    FileHandle    ;File handle
PUSH@  WORD    HandType      ;Handle type (returned)
PUSH@  WORD    FlagWord      ;Device driver attribute (returned)
CALL   DosQHandType

Returns WORD

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