This is part of Family API which allow to create dual-os version of program runs under OS/2 and DOS

Note: This is legacy API call. It is recommended to use 32-bit equivalent

DosClose

This call closes a handle to a file, pipe, or device.

Syntax

DosClose (FileHandle)

Parameters

FileHandle (HFILE) - input : Handle returned by a previous DosOpen, DosMakeNmPipe, or DosMakePipe call.

Return Code

rc (USHORT) - return

Return code descriptions are:

0 NO_ERROR

2 ERROR_FILE_NOT_FOUND

5 ERROR_ACCESS_DENIED

6 ERROR_INVALID_HANDLE

Remarks

Issuing DosClose with the handle to a file closes a handle to a file, pipe, or device.

If one or more additional handles to a file have been created with DosDupHandle, the directory is not updated and all internal buffers are not written to the medium until DosClose has been issued for the duplicated handles.

Closing a handle to a device causes the device to be notified of the close, if appropriate.

Named Pipe Considerations

DosClose closes a named pipe by handle. When all handles referencing one end of a pipe are closed, the pipe is considered broken.

If the client end closes, no other process can re-open the pipe until the serving end issues a DosDisConnectNmPipe followed by a DosConnectNmPipe.

If the server end closes when the pipe is already broken, it is deallocated immediately; otherwise, the pipe is not deallocated until the last client handle is closed.

Example Code

C Binding

#define INCL_DOSFILEMGR USHORT rc = DosClose(FileHandle); HFILE FileHandle; /* File handle */ USHORT rc; /* return code */

This example opens a file, then closes it.

#define INCL_DOSFILEMGR #define OPEN_FILE 0x01 #define CREATE_FILE 0x10 #define FILE_ARCHIVE 0x20 #define FILE_EXISTS OPEN_FILE #define FILE_NOEXISTS CREATE_FILE #define DASD_FLAG 0 #define INHERIT 0x80 #define WRITE_THRU 0 #define FAIL_FLAG 0 #define SHARE_FLAG 0x10 #define ACCESS_FLAG 0x02 #define FILE_NAME "test.dat" #define FILE_SIZE 800L #define FILE_ATTRIBUTE FILE_ARCHIVE #define RESERVED 0L HFILE FileHandle; USHORT Wrote; USHORT Action; PSZ FileData[100]; USHORT rc; Action = 2; strcpy(FileData, "Data..."); if(!DosOpen(FILE_NAME, /* File path name */ &FileHandle, /* File handle */ &Action, /* Action taken */ FILE_SIZE, /* File primary allocation */ FILE_ATTRIBUTE, /* File attribute */ FILE_EXISTS | FILE_NOEXISTS, /* Open function type */ DASD_FLAG | INHERIT | /* Open mode of the file */ WRITE_THRU | FAIL_FLAG | SHARE_FLAG | ACCESS_FLAG, RESERVED)) /* Reserved (must be zero) */ rc = DosClose(FileHandle); /* File Handle */

MASM Binding

EXTRN DosClose:FAR INCL_DOSFILEMGR EQU 1 PUSH WORD FileHandle ;File handle CALL DosClose

Returns WORD

Note

Text based on http://www.edm2.com/index.php/DosClose_(FAPI)

Family API
DOS	Process Manager	DosBeep DosExit DosSleep DosExecPgm
File Manager	DosChDir DosChgFilePtr DosClose DosDelete DosDupHandle DosMkDir DosMove DosQCurDir DosQCurDisk DosSetFileMode DosOpen DosQFileInfo DosRead DosQFileMode DosQFSInfo DosQVerify DosRmDir DosSelectDisk DosFindClose DosFindFirst DosFindNext DosSetFileInfo DosSetVerify DosWrite DosFileLocks DosSetFHandState DosNewSize DosBufReset DosQFHandState DosSetFSinfo DosShutdown
Memory Manager	DosFreeSeg DosSubAlloc DosSubFree DosSubSet DosAllocHuge DosAllocSeg DosReallocHuge DosReallocSeg DosGetHugeShift DosCreateCSAlias
NLS	DosCaseMap DosGetCtryInfo DosGetDBCSEv DosSetCtryCode DosGetCollate DosGetMessage DosInsMessage DosPutMessage
Date and Time	DosSetDateTime DosGetDateTime
Devices	DosDevConfig DosDevIOCtl DosDevIOCtl2
Signals	DosHoldSignal DosSetSigHandler
Misc	BadDynLink DosGetEnv DosGetMachineMode DosGetVersion DosError DosErrClass DosSetVec
KBD	KbdCharIn KbdFlushBuffer KbdGetStatus KbdSetStatus KbdStringIn KbdPeek
VIO	VioGetBuf VioGetConfig VioGetCurPos VioGetCurType VioGetPhysBuf VioReadCellStr VioReadCharStr VioScrollUp VioScrollDn VioScrollLf VioScrollRt VioScrUnLock VioSetCurPos VioSetCurType VioSetMode VioGetMode VioShowBuf VioWrtCellStr VioWrtCharStr VioWrtCharStrAtt VioWrtNAttr VioWrtNCell VioWrtNChar VioWrtTTY VioScrLock VioPopUp
Tools	BIND
Modules	DOSCALLS.DLL VIOCALLS.DLL KBDCALLS.DLL MSG.DLL
Libraries	API.LIB OS2386.LIB FAPI.LIB DOSCALLS.LIB SUBCALLS.LIB