View source for DevHlp CloseFile

DevHlp_CloseFile is used by base device drivers to close a file previously opened using DevHlp_OpenFile.
This devhlp closes a file opened by DevHlp_OpenFile.

==Syntax==
C
<PRE>
DevHlp_CloseFile ( PFILEIOINFO pFileClose)
</PRE>

Assembler
<PRE>
LES DI, FileClose
MOV DL, DevHlp_CloseFile

CALL [Device_Help]
</PRE>
==Parameters==
===C===
; pFILEIOINFO input : Pointer to the FILEIOINFO structure defined as follows

    typedef struct FOPEN {
            PSZ    FileName;   /* (input) pointer to file name */
            ULONG  FileSize;   /* (output) size of file returned by FileOPen */
    } FILEOPEN;

    typedef struct FCLOSE {
            USHORT  reserved   /* reserved */
    } FILECLOSE;

    typedef struct FREAD {
            PBYTE Buffer;      /* (input) pointer to input buffer */
            ULONG ReadSize;    /* (input) number of bytes to read fromfile */
    } FILEREAD;

    typedef struct FREADAT {
            PBYTE Buffer;        /* (input) pointer to input buffer */
            ULONG ReadSize;      /* (input) number of bytes to read from file */
            ULONG StartPosition  /* (input) starting file position relative to
                                     the beginning of the file */
    } FILEREADAT;

    typedef union FILEIOOP {
            struct FOPEN FileOpen;
            struct FCLOSE FileClose;
            struct FREAD FileRead;
            struct FREADAT FileReadAt;
    } FILEIOOP;

    typedef struc _DDFileIo {
            USHORT Length; /* (input) length of imbedded structure */
            FILEIOOP Data; /* (input) imbedded file system operation structure */
    } FILEIOINFO, FAR * PFILEIOINFO

===Assembler===
ES DI points to a FILEIOINFO structure defined as follows 
<PRE>
FILEIOINFO struc ; 
length          dw       2     ; length of imbedded fle system operation structure
                               ; must contain value 2 for CloseFile
FCLOSE struc
reserved        dw       ?     ; reserved
FCLOSE     ends
;
FILEIOINFO ends
</PRE>

====Data Structure===
<PRE>
; assembler structure
SYICloseFile	struc
length		dw	2	; length of structure (must be 2)
SYICloseFile	ends
</PRE>

==Return Code==

===C===
Success Indicator 0 if file was closed.
; 24 ERROR_BAD_LENGTH : Length in the FILEIOINFO structure is invalid.

===Assembler===
Results in Assembler

C Clear if the file is closed. AX = zero..

C Set if error. AX = Error Code. Possible errors

; 24 ERROR_BAD_LENGTH : The length in the FILEIOINFO structure is invalid.

==Errors== 

==Remarks==
DevHlp_FileClose may be called at initialization time only. It provides a primitive interface to the mini-IFS or micro_IFS at initialization.

Using this interface, one file only may be opened at a time. No handle is assigned by open. The file closed is assumed to be the most recent opened using DevHlp_OpenFile.

Valid at INIT time only. See also restrictions of [[DevHlp_OpenFile]].

==Example Code==

===C Sample===
<PRE>#include  "dhcalls.h"

USHORT APIENTRY DevHlp_CloseFile

    ( PFILEIOINFO pFileClose) 

pFILEIOINFO input

    Pointer to the FILEIOINFO structure defined as follows

    typedef struct FOPEN {
            PSZ    FileName;   /* (input) pointer to file name */
            ULONG  FileSize;   /* (output) size of file returned by FileOPen */
    } FILEOPEN;

    typedef struct FCLOSE {
            USHORT  reserved   /* reserved */
    } FILECLOSE;

    typedef struct FREAD {
            PBYTE Buffer;      /* (input) pointer to input buffer */
            ULONG ReadSize;    /* (input) number of bytes to read fromfile */
    } FILEREAD;

    typedef struct FREADAT {
            PBYTE Buffer;        /* (input) pointer to input buffer */
            ULONG ReadSize;      /* (input) number of bytes to read from file */
            ULONG StartPosition  /* (input) starting file position relative to
                                     the beginning of the file */
    } FILEREADAT;

    typedef union FILEIOOP {
            struct FOPEN FileOpen;
            struct FCLOSE FileClose;
            struct FREAD FileRead;
            struct FREADAT FileReadAt;
    } FILEIOOP;

    typedef struc _DDFileIo {
            USHORT Length; /* (input) length of imbedded structure */
            FILEIOOP Data; /* (input) imbedded file system operation structure */
    } FILEIOINFO, FAR * PFILEIOINFO

</PRE>

Assembler
<PRE>
LES DI, FileClose
MOV DL, DevHlp_CloseFile

CALL [Device_Help]
</PRE>

==Related Functions==

[[Category:DevHlps]]