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FWrite Function

X#
Write a string to an open file.

Namespace:  XSharp.RT
Assembly:  XSharp.RT (in XSharp.RT.dll) Version: 2.19
Syntax
 FUNCTION FWrite(
	ptrHandle,
	cBuffer,
	nBytes
) AS DWORD CLIPPER
Request Example View Source

Parameters

ptrHandle (Optional)
Type: Usual
The handle of the file to write to.
cBuffer (Optional)
Type: Usual
The string to write.
nBytes (Optional)
Type: Usual
The number of bytes in cBuffer to write, beginning at the current file pointer position.
If omitted, the entire contents of cBuffer is written.

Return Value

Type: DWord
The number of bytes written.
If the value returned is equal to nBytes, the operation was successful.
If the return value is less than nBytes or 0, this means that the length of cBuffer is less than nBytes, or the disk is full, or another error has occurred. FError() can be used to determine the specific error. When a disk full error occurs, FError() is set to 256. FWrite() and FWrite3 are assumed to handle raw binary data and are not dependent upon the status of SetAnsi(). FWriteText() and FWrite4(), on the other hand, are dependent upon SetAnsi().
Remarks
Remarks
Tip Tip
This function is included for compatibility. We do not recomment using static memory for file i/o operations. We recommend that you use the function overload that takes a byte array parameter in stead.
Examples
This example copies the contents of one file to another:
X#
 1DEFINE F_BLOCK := 512
 2...
 3cBuffer := Space(F_BLOCK)
 4nInfile := FOpen2("temp.txt", FO_READ)
 5nOutfile := FCreate("newfile.txt", FC_NORMAL)
 6lDone := FALSE
 7DO WHILE !lDone
 8    nBytesRead := FRead(nInfile, @cBuffer,;
 9    F_BLOCK)
10    IF FWrite(nOutfile, cBuffer) < SLen(cBuffer)
11        ? DOSErrString(FError())
12        lDone := TRUE
13    ELSE
14        lDone := (nBytesRead = 0)
15    ENDIF
16ENDDO
17FClose(nInfile)
18FClose(nOutfile)
See Also