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REMOVE() in RTL has bugs and is very slow using ShFileOperation(). My replacement uses API DeleteFile() and sets Clarion ErrorCode() so can replace REMOVE().
!There are a few Remove() things here, what you want is FileApiRemove FUNCTION(STRING Fn2Delete),LONG,PROC
!
!In C8 Clarion REMOVE() was enhanced a second parameter with flags to allow wildcards, recursion, etc
!It was changed from calling API DeleteFile() to use the much more complicated ShFileOperation()
!This makes it much slower and more bug prone
!
!My replacement FileApiRemove() uses API DeleteFile() then sets the Claion Error so it can replace
!an existing REMOVE() in Clarion code. If you are using Remove(FILE) you'll need REMOVE(Name(File))
!or you can create a FileApi2Remove(FILE FileRef) that calls FileApiRemove(FileRef{PROP:Name}) or NAME()
!I named it "FileApiRemove(" so if you are searching "REMOVE(" you'll file it, versus RemoveUsingAPI() would not.
!
!One Other PITA with REMOVE() is if its a TPS file the Driver will open the file and read the header in case its a super file.
!Often if you are changing the file, e.g. to add an OWNER password, you can get an error when Remove(Name(TpsFile)) will work.
!--------------------------------------------------------------
PROGRAM
INCLUDE 'TplEqu.CLW'
INCLUDE 'KeyCodes.CLW'
MAP
TestWindow PROCEDURE()
FileApiRemove FUNCTION(STRING Fn2Delete),LONG,PROC !API Replacement 0=OK else GetLastError(). Can ignore sets RTL ErrorCode()
SafeRemove FUNCTION(STRING Fn2Delete) !Uses DOS File with RTL REMOVE()
TestRemoveFileAPI FUNCTION(STRING Fn2Delete)
RemoveFileQueue FUNCTION(FILE:Queue FlzQ, STRING _FilePath),LONG,PROC !Returns files left
MODULE('ClaApi')
!These Error functions have been in the RTL forever and appear in LibSrc but are not documented
SetError(LONG ErrNumberToSet),NAME('Cla$SetError'),DLL(DLL_Mode)
ClearError(),NAME('Cla$ClearError'),DLL(DLL_Mode)
MkDir(*cstring),short,raw,proc,name('_mkdir'),DLL(DLL_Mode) !just used in this test
end
module('api')
DeleteFile(*CSTRING lpFileName),PASCAL,DLL(1),RAW,BOOL,PROC,name('DeleteFileA')
OutputDebugString(*CSTRING cMsg),PASCAL,DLL(1),RAW,NAME('OutputDebugStringA')
DebugBreak(),PASCAL,DLL(1) !If running under Debug forces the debugger to popup
GetLastError(),LONG,PASCAL,DLL(1)
Sleep(LONG),PASCAL,DLL(1)
end
end
code
TestWindow()
return
!===============================================================================
TestWindow PROCEDURE()
TestFolderBS CSTRING('.\TestDelPath\')
DelDolQ QUEUE(FILE:Queue),PRE(DelDoDelDolQlQ)
END
Window WINDOW('Delete File API'),AT(,,566,276),CENTER,GRAY,SYSTEM,FONT('Segoe UI',9),RESIZE
STRING('Buttons test FileApiRemove()'),AT(11,23)
BUTTON('Remove IdoNOTexist.$$$'),AT(11,37),USE(?DeleteNEfile)
BUTTON('Remove badpath\na.$$$'),AT(11,52),USE(?DeletebadPathfile)
BUTTON('Remove m:\badpath\na.$$$'),AT(11,67),USE(?DeleteMdrvBadPathfile)
BUTTON('Remove TestReadOnly.$$$'),AT(11,82),USE(?DeleteReadOnly)
BUTTON('Test SafeRemove()'),AT(11,109),USE(?SafeRemoveTEstBtn)
STRING('Path:'),AT(7,6),USE(?STRINGpath)
LIST,AT(157,23),FULL,USE(?ListFiles),VSCROLL,TIP('Click heads to sort, right click to reverse'), |
FROM(DelDolQ),FORMAT('100L(1)|M~Name~@s255@52L(1)|M~Short Name~@s13@40R(1)|M~Date~C(' & |
'0)@d1@40R(1)|M~Time~C(0)@T4@56R(1)|M~Size~C(0)@n13@16L(1)|M~Attr~@n3@'), |
ALRT(MouseLeft), ALRT(MouseRight)
BUTTON('Load Random'),AT(207,4),USE(?FQloadRandomBtn),TIP('Create 50 Temp files with PUTINI ' & |
'named TD####.$$$ in .\TestDelPath\')
BUTTON('Delete Q'),AT(275,4),USE(?FQDeleteBtn),TIP('Delete Temp files in LIST below using Re' & |
'moveFileQueue()')
END
code
MkDir(TestFolderBS)
open(window)
?STRINGpath{PROP:Text}=longpath()
accept
case event()
end
case accepted()
OF ?DeleteNEfile ; TestRemoveFileAPI('IdoNotExist.$$$')
OF ?DeletebadPathfile ; TestRemoveFileAPI('badpath\na.$$$')
OF ?DeleteMdrvBadPathfile ; TestRemoveFileAPI('m:\badpath\na.$$$')
OF ?DeleteReadOnly ; IF ~EXISTS('TestReadOnly.$$$') THEN Message('You must create a file and make Read Only file named: TestReadOnly.$$$','Action').
TestRemoveFileAPI('TestReadOnly.$$$')
OF ?SafeRemoveTEstBtn ; DO SafeRemoveTEstRtn
OF ?FQloadRandomBtn ; DO FQloadRandomRtn
OF ?FQDeleteBtn ; DO FQDeleteRtn
end
end
close(window)
SafeRemoveTEstRtn ROUTINE
DATA
DelFN STRING('.\SafeTest.INI')
cFold CSTRING(260)
cFold2 CSTRING(260)
WhatTest PSTRING(256)
CODE
PUTINI('xxx','yyy','1',DelFN)
e1#=EXISTS(DelFN)
SafeRemove(DelFN)
e2#=EXISTS(DelFN)
Message('SafeRemove(Safetest.INI) ' & choose(e1#=1 and e2#=0,' WORKED! ', 'Unexpected Exists Before=' & E1# & 'After=' & E2#) )
!Wildcard test
PUTINI('xxx','yyy','1','.\SafeTest1.INI')
PUTINI('xxx','yyy','1','.\SafeTest2.INI')
PUTINI('xxx','yyy','1','.\SafeTest3.INI')
Message('Testing Wildcards SafeRemove(SafeTest*.INI)',LONGPATH())
SafeRemove('SafeTest*.INI')
IF EXISTS('SafeTest1.INI') AND EXISTS('SafeTest2.INI') THEN
SafeRemove('SafeTest1.INI') ; SafeRemove('SafeTest2.INI')
ELSE
Message('PROBLEM! Wildcards worked SafeRemove(SafeTest*.INI)')
END
!Wildcard in folder test
cFold ='SafeWildTest' & clock()
MkDir(cFold) ; e1#=EXISTS(cFold) ; IF ~e1# THEN STOP('Failed MkDir ' & CFold) .
PUTINI('xxx','yyy',CLOCK(),cFold & '\SafeFldTest1.INI')
PUTINI('xxx','yyy',CLOCK(),cFold & '\SafeFldTest2.INI')
Message('Read to test SafeRemove(' & cFold & '\SafeFldTest*.INI' )
SafeRemove(cFold & '\SafeFldTest*.INI')
Message('Are files gone? SafeRemove(' & cFold & '\SafeFldTest*.INI' )
!Folder tests
cFold ='SafeRmvTest' & day(today())&clock()
MkDir(cFold)
e1#=EXISTS(cFold) ; IF ~e1# THEN STOP('Failed MkDir ' & CFold) .
CASE Message('Test What','SafeRemove(Folder) Test',,'HALT()|Empty|Has Files|Sub-Folders') -1
OF 0 ; HALT()
OF 1
WhatTest='Empty folder Remove'
OF 2
WhatTest='Folder with INI File'
PUTINI('xx',TODAY(),Clock(), '.\' & cFold & '\TestRemoveFolder.ini')
Message('Ready to test SafeRemove(Folder) folder has 1 INI file)||' & cFold , LongPath() )
OF 3
WhatTest='Folder with SubFolder'
cFold2 = CFold & '\SubFolder' & random(100,999)
MkDir(cFold2)
IF ~EXISTS(cFold2) THEN STOP('Failed MkDir ' & CFold2) .
Message('Ready to test SafeRemove(Folder)| ' & cFold&'||Sub ' & CFold2 , LongPath() )
END
SafeRemove(cFold)
e2#=EXISTS(cFold)
Message('SafeRemove(SafeRmvFolderTest)|Test=' & WhatTest &'||'& |
choose(e1#=1 and e2#=1,' Worked, folder exists '& cFold,'') & |
choose(e1#=1 and e2#=0,' FAILED, Got Removed! ', '') & |
choose(e1#=0 ,' Failed to MkDir(' & cFold ,'') & |
'', longpath())
EXIT
FQloadRandomRtn ROUTINE
!FYI TestFolderBS = '.\TestDelPath\'
loop 50 TIMES
putini(today(),clock(),1,TestFolderBS & 'td' & random(1,1000000) & '.$$$')
end
FREE(DelDolQ)
DIRECTORY(DelDolQ,TestFolderBS & 'TD*.$$$',ff_:NORMAL)
DISPLAY
EXIT
!------------------
FQDeleteRtn ROUTINE
RemoveFileQueue(DelDolQ,TestFolderBS)
!===============================================
TestRemoveFileAPI FUNCTION(STRING Fn2Delete)
CODE
message('Test FileApiRemove()||File: ' & Fn2Delete & |
'||FileApiRemove() Return=' & FileApiRemove(Fn2Delete) & |
'||Clarion ErrorCode()=' & ErrorCode() & |
'|Clarion Error()='& Error(),'TestRemoveFileAPI()',ICON:Asterisk )
return
!===================================================================================================
RemoveFileQueue FUNCTION(FILE:Queue FlzQ, STRING _FilePath)!,LONG,PROC !Returns files left
pFilePathBS PSTRING(255),AUTO
LnFP LONG,AUTO
Ndx LONG,AUTO
Ret SHORT
KillTry SHORT !#cc-283# delete timing issues
LastTry EQUATE(4) !#cc-283#
CODE
LnFP=LEN(CLIP(_FilePath))
IF ~LnFP THEN
pFilePathBS='.\'
ELSE
pFilePathBS=_FilePath[1 : LnFP] & choose(_FilePath[LnFP]='\','','\') !add ending "\" if needed
END
!message(_FilePath &'|' & pFilePathBS )
LOOP KillTry = 1 TO LastTry !#cc-283# try 5 tiems to delete all the files
LOOP Ndx = RECORDS(FlzQ) TO 1 BY -1 !#cc-283# go backwards to allow delete(q) 1 TO RECORDS(FlzQ)
GET(FlzQ,Ndx)
EXECUTE Killtry % 2 + 1 !Alternate API Remove and Clarion Remov
Remove(pFilePathBS & FlzQ:Name ) !KillTry 2 4 so % 2 + 1 = 1
FileApiRemove(pFilePathBS & FlzQ:Name ) !KillTry 1 3 so % 2 + 1 = 2
END
CASE ERRORCODE()
OF 0 OROF 2 OROF 3 !No error, no file, no path, that's fine
DELETE(FlzQ) !#cc-283# delete from queue if worked so I know I'm ok
ELSE
!I failed
END !Case Error
END !Loop Ndx Q
IF ~RECORDS(FlzQ) THEN BREAK.
SLEEP(100)
GET(FlzQ,1)
IF EXISTS(pFilePathBS & FlzQ:Name ) THEN !on one system doing an Exists() helped
END
END ! LOOP KillTry = 1 TO LastTry !#cc-283# no need for 5 tries if Q is empty
RETURN RECORDS(FlzQ)
!===================================================================================================
! Another idea use the DOS driver to Remove(). I would not do this.
!===================================================================================================
SafeRemove FUNCTION (STRING Fn2Delete)
File2Rmv FILE,DRIVER('DOS') !Any Driver works
RECORD ; END
END
CODE
!Warning: Removes Empty Folders, but not filled (for me)
File2Rmv{PROP:Name}=Fn2Delete
REMOVE(File2Rmv)
RETURN
!===================================================================================================
! FileApiRemove() replacement for Clarion REMOVE() in that it sets the ErrorCode() and Error().
! This also returns the API GetLastError() or Zero for Success
!===================================================================================================
FileApiRemove FUNCTION (STRING Fn2Delete)!,LONG,PROC !0=ok, else returns Error code, also sets RTL ERRORCODE() ERROR()
cFN CSTRING(261),AUTO
ApiError LONG !GetLastError() when DeleteFile() fails
ClarionErr LONG !Api Error converted to matching Clarion Error number
CODE
cFN=clip(Fn2Delete)
IF 0=DeleteFile(cFn) THEN !Return 0 = Failed to DeleteFile() see GetLastError() for why
ApiError=GetlastError()
IF ~ApiError THEN ApiError=1. !Return says Failed, but no error ... so set something, should never happen
ClarionErr = ApiError !Most Clarion Error Numbers are the same as API Error Number
CASE ApiError !Translate some unusual GLE to errors to Clarion
OF 32 ; ClarionErr = 52 !API ERROR_SHARING_VIOLATION 32 (0x20) The process cannot access the file because it is being used by another process.
! Clarion Help says Error 52 = File Already Open - An attempt to OPEN a file that has already been opened by this user.
END
SetError(ClarionErr) !Set Error in RTL so caller can use ERRORCODE() just like if used RTL REMOVE()
ELSE !non-zero return from DeleteFile() means it worked and file was deleted
ClearError() !Delete worked set Error to Zero (close) in RTL so caller can use ERRORCODE()
END
RETURN ApiError !Return is Optional (PROC) so caller can check API Error Code if desired
!--------------------------------------------
!Possible enhancement, if fails could Sleep(100) and retry 5 times, file may have
!just been closed and Virus scanner is looking at it, or OS is catchng up to commit delete
!
!SQLite has notes about exactly this problem.
! #define MX_DELETION_ATTEMPTS 5
! do{
! DeleteFileA(zConverted);
! }while( ( ((rc = GetFileAttributesA(zConverted)) != INVALID_FILE_ATTRIBUTES)
! || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
! && (++cnt < MX_DELETION_ATTEMPTS)
! && (Sleep(100), 1) );
!---------------------------------------------
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