The following function will remove invalid characters from a file name (w/o path)

FUNCTION MakeFileNameValid(tcFileName)
* Removes invalid characters from a file name)
RETURN ALLTRIM(CHRTRAN(tcFileName, GetInvalidFileNameChars(), ""), " ", ".")

FUNCTION GetInvalidFileNameChars()
LOCAL lcInvalidFileNameChars, lnAsc
lcInvalidFileNameChars = ["*/:<>?\|]
FOR lnAsc=0 TO 31
	lcInvalidFileNameChars = lcInvalidFileNameChars + CHR(lnAsc)
ENDFOR
RETURN lcInvalidFileNameChars

Below are Windows limitation on file/path pulled from Windows SDK header file

* max. length of full pathname 
#define _MAX_PATH   260 
* max. length of path component 
#define _MAX_DIR    256 
* max. length of file name component
#define _MAX_FNAME  256 
* max. length of extension component
#define _MAX_EXT    256 

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>I have a small program that gets 3 portions of a file path from comboboxes and the 4th is a textbox that is supposed to be the file name.
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>How can I convert any invalid characters put in these portions to filename safe string. Plus what is the maximum length of a relative pathname ?
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