This call sets attribute and extended attribute information for a file.


DosSetFileInfo (FileHandle, FileInfoLevel, FileInfoBuf, FileInfoBufSize)


;FileHandle (HFILE) - input : File handle. ;FileInfoLevel (USHORT) - input : Level of file information being set. A value of 1 or 2 can be specified. The structures described in FileInfoBuf indicate the information being set for each of these levels. ;FileInfoBuf (PBYTE) - input : Address of the storage area containing the structures for file information levels.

'Level 1 Information' FileInfoBuf contains the following structure, to which information is specified in the following format:

filedate (FDATE) : Structure containing the date of file creation. 'Bit Description' 15-9 Year, in binary, of file creation 8-5 Month, in binary, of file creation 4-0 Day, in binary, of file creation. filetime (FTIME) : Structure containing the time of file creation. 'Bit Description' 15-11 Hours, in binary, of file creation 10-5 Minutes, in binary, of file creation 4-0 Seconds, in binary number of two-second increments, of file creation. fileaccessdate (FDATE) : Structure containing the date of last access. See FDATE in filedate.

fileaccesstime (FTIME) : Structure containing the time of last access. See FTIME in filetime.

writeaccessdate (FDATE) : Structure containing the date of last write. See FDATE in filedate.

writeaccesstime (FTIME) : Structure containing the time of last write. See FTIME in filetime.

filesize (ULONG) : File size.

filealloc (ULONG) : Allocated file size.

fileattrib (USHORT) : Attributes of the file, defined in DosSetFileMode.

'Level 2 Information'

FileInfoBuf contains an EAOP structure, which has the following format:

fpGEAList (PGEALIST) : Address of GEAList. GEAList is a packed array of variable length “get EA” structures, each containing an EA name and the length of the name.

fpFEAList (PFEALIST) : Address of FEAList. FEAList is a packed array of variable length “full EA” structures, each containing an EA name and its corresponding value, as well as the lengths of the name and the value.

oError (ULONG) : Offset into structure where error has occurred.

Level 2 sets a series of EA name/value pairs. On input, FileInfoBuf is an EAOP structure above. fpGEAList is ignored. fpFEAList points to a data area where the relevant FEA list is to be found. oError is ignored. Following is the format of the FEAList structure:

cbList (ULONG) : Length of the FEA list, including the length itself.

list (FEA) : List of FEA structures. An FEA structure has the following format:

Flags (BYTE) : Bit indicator describing the characteristics of the EA being defined.

'Bit Description' 7 Critical EA. 6-0 Reserved and must be set to zero.

If bit 7 is set to 1, this indicates a critical EA. If bit 7 is 0, this means the EA is noncritical; that is, the EA is not essential to the intended use by an application of the file with which it is associated.

cbName (BYTE) : Length of EA ASCIIZ name, which does not include the null character.

cbValue (USHORT) : Length of EA value, which cannot exceed 64KB.

szName (PSZ) : Address of the ASCIIZ name of EA.

aValue (PSZ) : Address of the free-format value of EA.

'Note:' The szName and aValue fields are not included as part of header or include files. Because of their variable lengths, these entries must be built manually.

On output, fpGEAList is unchanged. fpFEAList is unchanged as is the area pointed to by fpFEAList. If an error occurred during the set, oError is the offset of the FEA where the error occurred. The API return code is the error code corresponding to the condition generating the error. If no error occurred, oError is undefined.

; FileInfoBufSize (USHORT) - input : Length of FileInfoBuf.

Return Code



DosSetFileInfo is successful only when the file is opened for write access, with a deny-both sharing mode specified for access to the file by other processes. If the file is already opened with conflicting sharing rights, the call to DosOpen or DosOpen2 will fail.

A 0 value in the date and time components of a field does not change the field. For example, if both “last write date” and “last write time” are specified as 0 in the Level 1 information structure, then both attributes of the file are left unchanged. If either “last write date” or “last write time” are specified as non-zero, both attributes of the file are set to the new values.

The FAT file system supports modification of only the dates and times of the last write. Creation and last access dates and times are not affected.

The last modification date and time will get changed if the extended attributes are modified.

Family API Considerations

It is not possible to create a label with leading blank characters in DOS mode, because of restrictions on the previous Interrupt 21h function call (create an FCB type file), which must be used by FAPI.

Example Code

C Binding

<PRE> typedef struct _FDATE { /* fdate */

unsigned day : 5; /* binary day for directory entry */

unsigned month : 4;     /* binary month for directory entry */
unsigned year  : 7;     /* binary year for directory entry */


typedef struct _FTIME { /* ftime */

unsigned twosecs : 5; /* binary number of two-second increments */

unsigned minutes : 6;       /* binary number of minutes */
unsigned hours   : 5;       /* binary number of hours */


typedef struct _FILESTATUS { /* fsts */

FDATE fdateCreation; /* date of file creation */

FTIME  ftimeCreation;        /* time of file creation */
FDATE  fdateLastAccess;      /* date of last access */
FTIME  ftimeLastAccess;      /* time of last access */
FDATE  fdateLastWrite;       /* date of last write */
FTIME  ftimeLastWrite;       /* time of last write */
ULONG  cbFile;               /* file size (end of data) */
ULONG  cbFileAlloc;          /* file allocated size */
USHORT attrFile;             /* attributes of the file */


typedef struct _GEA { /* gea */

BYTE cbName; /* name length not including NULL */

CHAR szName[1];         /* attribute name */

} GEA;

typedef struct _GEALIST { /* geal */

ULONG cbList; /* total bytes of structure including full list */

GEA list[1];            /* variable length GEA structures */


typedef struct _FEA { /* fea */

BYTE fEA; /* flags */

BYTE cbName;            /* name length not including NULL */
USHORT cbValue;         /* value length */

} FEA;

typedef struct _FEALIST { /* feal */

ULONG cbList; /* total bytes of structure including full list */

FEA list[1];            /* variable length FEA structures */


typedef struct _EAOP { /* eaop */

PGEALIST fpGEAList; /* general EA list */

PFEALIST fpFEAList;     /* full EA list */
ULONG  oError;



USHORT rc = DosSetFileInfo(FileHandle, FileInfoLevel, FileInfoBuf,


HFILE FileHandle; /* File handle */ USHORT FileInfoLevel; /* File info data required */ PBYTE FileInfoBuf; /* File info buffer */ USHORT FileInfoBufSize; /* File info buffer size */

USHORT rc; /* return code */


MASM Binding

<PRE> FDATE struc

fdate_fs dw ?

FDATE ends

FTIME struc

ftime_fs dw ?

FTIME ends


fsts_fdateCreation dw (size FDATE)/2 dup (?) ;date of file creation

fsts_ftimeCreation   dw (size FTIME)/2 dup (?) ;time of file creation
fsts_fdateLastAccess dw (size FDATE)/2 dup (?) ;date of last access
fsts_ftimeLastAccess dw (size FTIME)/2 dup (?) ;time of last access
fsts_fdateLastWrite  dw (size FDATE)/2 dup (?) ;date of last write
fsts_ftimeLastWrite  dw (size FTIME)/2 dup (?) ;time of last write
fsts_cbFile          dd  ? ;file size (end of data)
fsts_cbFileAlloc     dd  ? ;file allocated size
fsts_attrFile        dw  ? ;attributes of the file


GEA struc

gea_cbName db ? ;name length not including NULL

gea_szName      db  1 dup (?)  ;attribute name

GEA ends


geal_cbList dd ? ;total bytes of structure including full list

geal_list       db  size GEA * 1 dup (?) ;variable length GEA structures


FEA struc

fea_fEA db ? ;flags

fea_cbName      db  ? ;name length not including NULL
fea_cbValue     dw  ? ;value length

FEA ends


feal_cbList dd ? ;total bytes of structure including full list

feal_list       db  size FEA * 1 dup (?) ;variable length FEA structures


EAOP struc

eaop_fpGEAList dd ? ;general EA list

eaop_fpFEAList  dd  ? ;full EA list
eaop_oError     dd  ? ;

EAOP ends


PUSH WORD FileHandle ;File handle PUSH WORD FileInfoLevel ;File info data required PUSH@ OTHER FileInfoBuf ;File info buffer PUSH WORD FileInfoBufSize ;File info buffer size CALL DosSetFileInfo

Returns WORD </PRE>


en/docs/fapi/dossetfileinfo.txt · Last modified: 2020/12/04 13:58 by prokushev