Compiled by Mike Dickason [72711,3404]
August  3, 1992     Initial posting   Bugs 1-12
August 11, 1992     Second posting    Bugs 13-19
August 17, 1992     Third posting     Bugs 20-24
August 31, 1992     Fourth posting    Bugs 25-29
September 12, 1992  Fifth posting     Bugs 30-44
October 11, 1992    Sixth posting     Bugs 45-50 Updated for R12c1

The following list of ACAD 12 bugs and corresponding work arounds
was compiled from a combination of problems I have personally
encountered and from messages posted on the ACAD forum of
Compuserve.  I am not an employee of AutoDesk, nor did I compile
this list to discredit AutoDesk.  Indeed, I am quite happy with
R12, but as with any program of this size and magnitude, there are
some bugs.

This is not an official nor a complete list of R12 bugs.  It is
meant to be used as an informative list to help other users who
might be encountering similar problems.  All of the problems on
this list have been reported to and acknowledged by ADESK.  If you
know of any bugs which are not included on this list, I would be
interested in hearing about them, solely for the purpose of keeping
the list up to date.  Unless noted otherwise, the bugs are present
in the North American version of ACAD R12c1 for DOS. 

Numbers prefixed with an '*' are either new to this posting, or
have been updated from the previous posting to include additional
information.  Those bugs fixed with the release of R12c1 have been
noted as such.

*1.  If you run any command which accepts the new fence selection
     option to select items (like the trim command), any subsequent
     usage of the lisp function (ssget "f" (list p1 p2)) will
     generate a heap error and will either instantly reboot the
     computer or dump you out of the editor to the DOS prompt
     without saving your drawing.  Fixed in R12c1.

 2.  Lantastic bug with DOS 5.0 and R12.  Unable to run ACAD across
     the network, or edit any drawing located on the network
     without generating sharing violation errors.  

     To solve the problem, download the file R12LAN.ZIP from the
     forum.  This patch allows AutoCAD to run on various  
     networks, including LANtastic, 3Com and DEC Pathworks, under
     DOS 4.0 and  5.0. See the README.DOC file included in the
     archive for specific instructions on how to use the patch. 
     This patch is still required for R12c1.

*3.  The Hitachi HDG driver shipping with R12 does not work with
     the Hitachi HDG 1111C and possibly earlier models.  Need to
     download the file DG386.EXP from here on the forum.  Fixed in
     R12c1.

*4.  The display filters for color with the DDLMODES command in R12
     don't recognize the ~ wildcard.  If you specify the color
     filter as W*, only those layers which have a color beginning
     with the letter 'w' are displayed, as expected.  But if you
     specify the wildcard as ~W*, all of the layers are displayed
     instead of only those which don't have a color beginning with
     the letter 'w'.  No known work around.

*5.  The layer DEFPOINTS is supposed to be an unplottable layer,
     but in R12 it is showing up on plots, regardless of whether it
     is turned on or off.  Fixed in R12c1.

 6.  When Release 12 compiles a PFB PostScript font file into an
     SHX font file, it makes the font approximately 30% too small. 
     If you insert some text with a regular AutoCAD font (such as
     Simplex) with a height of 2.5", it is drawn 2.5" inches tall.
     If you insert text with a converted PostScript font with a
     height of 2.5", it is drawn 1.7" high.  No known work around.

 7.  The path to the R12 drivers is stored within the ACAD.CFG
     file.  If you change rename the ACAD directory, or move it to
     a different location, then attempt to reconfigure ACAD using
     the "-R" switch, it will not find any drivers because it looks
     at the path stored in ACAD.CFG instead of the environment
     variable ACADDRV.  The only workaround is to delete the
     ACAD.CFG file and reconfigure ACAD.

 8.  When plotting with R12, if you use a plot scale of 1/8=12, the
     plot dialogue box rounds the scale off to the nearest tenth
     and displays the plot scale as 0.13=12.  It also plots the
     drawing at that scale.  Use 1=96 to get a 1/8" plot scale.  

*9.  When you try to plot a R10 drawing it works just fine if you
     bring up the drawing in the editor.  If you use the
     freeplotting feature by calling acad with a -P then it crashes
     with a EREAD error.  The only workaround is to plot from
     within the editor.  Fixed in R12c1.

*10. The Calcomp plotter driver shipping with R12 produces erratic
     plots under various situations.  Download the updated driver
     PLPCC.EXP from here on the forum.  Fixed in R12c1.

 11. The HP-GL2 plotter driver has a problem handling smart fills. 
     and will exhibit problems with filled areas such as plines
     with a width.  The only known work around is to use an HP-GL2
     driver written for R11.

 12. Here's a minor bug with R12's help command.  Run the help
     command, and select "Index" from the opening dialog box. 
     Double click on any item in the index list (I'll use 3D as the
     example) and the help screen for that item comes up as
     expected.  Now select "Index" again and the index dialog pops
     up with the selected item still highlighted.  Select "OK" to
     view the same item again and you get a prompt that says
     "Nothing selected." even though the item is still highlighted. 
     To get the item again, you have to physically select it
     instead of just selecting "OK".

 13. If you perform a PEDIT Join command on a polyline containing
     curve information, the resultant joined polyline is stripped 
     of all the curve information leaving you with a polyline made
     entirely of straight line segments.  No known workaround.

 14. With a closed polyline, if you perform the sequence PEDIT,
     Edit vertex, Break, the command will not only break out the
     segment between the specified vertices, but it also removes
     the "closing" segment of the polyline leaving you with two
     separate polylines if you attempt to break out an interior
     section.  No known workaround.  Note:  This problem occurred
     in earlier versions of ACAD and is not unique to R12.

*15. There is a problem in the plot command when specifying MM as
     the plot units. If you change any of the default pen widths,
     each time you go into the pen parameters menu, the pen widths
     are multiplied by 25.4.  This eventually leads to a general
     protection fault and ACAD crashing.  Fixed in R12c1.

     To show this, run the plot command, set the units to MM, then
     select Pen Assignments.  Start clicking on pen 1, and watch
     the width display in the bottom right corner.  Each time it
     increments by a factor of 25.4. Click on pen 1 twenty six
     times, then select OK, then immediately select Pen Assignments
     again.  You will get "FATAL ERROR: General protect exception"
     which immediately returns you to the DOS prompt without saving
     the drawing.  Again, this is fixed in R12c1.

*16. When plotting units are set to MM, retrieving a pcp file
     results in the paper size being multiplied by 25.4, even if
     the pcp was stored with MM units.  No known work around.  When
     restoring plot defaults from a file, make sure to check the
     paper size before you plot.  Fixed in R12c1.

 17. There is a problem with certain DIMVARS when DIMSCALE is not
     set to 1.  It affects all DIM variables with distance-type
     values, like DIMCEN, DIMTXT, DIMASZ, etc.  With these
     variables, if you are in the DIM command and you type in the
     variable name (like DIMCEN) and hit enter to take the default,
     the default value is divided by the value of DIMSCALE and the
     result becomes the new default.  You can avoid the problem for
     now by setting DIM vars outside the DIM command (like other
     system variables), or by retyping the default value rather
     than using ENTER to retain it.

 18. When using the new Shift to Add feature for building selection
     sets, the "Window" and "Crossing" selection options add to the
     current selection set instead of replacing it as documented. 
     No known work around.

 19. If you perform a Dview Twist on a drawing, then plot with a
     window, the coordinates of the window corners displayed in the
     new plot dialog box do not match the actual coordinates that
     were picked.  Regardless of what the plot window shows, the
     actual coordinates picked are used for generating the plot. 
     This appears to related to the variable "TARGET", which
     changes after a DVIEW, but never seems to be set back to its
     default value (i.e. start a new drawing, look at the value of
     TARGET, then do a Dview Twist 300, Dview Twist 0, and then
     look at TARGET again and it is different).  No known work
     around.

 20. There is a bug with variable width polylines and the commands
     PEDIT and Undo.  If you have a variable width polyline, then
     perform a Pedit on it and change the width to 0, then at the
     command prompt do an Undo which backs through the Pedit, the
     starting and ending widths of the first segment of the
     polyline will be applied to the entire polyline.  The
     following sequence demonstrates the problem:
  Command: PLINE
  From point: 0,0
  Current line-width is 0'-0"
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: W
  Starting width <0'-0">: 0
  Ending width <0'-0">: 3
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 0,0
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: W
  Starting width <0'-3">: 0
  Ending width <0'-0">: 0
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 10,10
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 20,10
 
  Command: PEDIT
  Select polyline: Last
  Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltypegen/Undo/eXit <X>: W
  Enter new width for all segments: 0
  Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltypegen/Undo/eXit <X>: X
 
  Command: U

  No known workaround.

*21. Here is a bug with the R12 menu command.  With FILEDIA=0, run
     the Menu command and type in the name of a non-existent menu. 
     ACAD will report that it can't open the file and display the
     search path used.  It then prompts "Enter another menu file
     name (or RETURN for none):".  If you hit the return button on
     the digitizer instead of the keyboard, you will get a       
     "FATAL ERROR: Null pointer referenced"
          "Do you want to save your changes?  <Y> "

     The workaround is to use the keyboard for hitting the Enter
     key.  Fixed in R12c1.

 22. There is a problem with the pen parameters dialog box in the
     R12 plot command.  The program is handling pens in groups of
     10, ie. 1-10, 11-20, 21-20, etc.  If you make a change to any
     of the pen parameters for pens 11-256, the corresponding pen
     in group 1-10 is changed as well.  For example, change pen 11
     to have a width of 1.0, then scroll up and look at pen 1.  Its
     width will have changed to 1.0 as well.  It also works the
     other way.  Change pen 1 and pen 11 changes, and pen 21
     changes, etc.  No known workaround.

 23. R12 has a problem with Wblocks and file locking when using
     relative paths to specify the drawing name.  With file locking
     turned on, if I open a file with a relative path, then attempt
     to Wblock the drawing back to itself using the same relative
     path, ACAD reports the following error message:

         Unable to lock file .\MIKE
         File write locked by USER1
         at 10:00 on 08/13/1992

          The command sequence to show this...

               Command:     OPEN
               File name:   .\MIKE
               Command:     WBLOCK
               File name:   .\MIKE

     R11 didn't exhibit this problem.  The only way to make it work
     in R12 is to type out the full path for the Wblock name, which
     is a pain when you have long paths for the file directories. 
     
     The same problem occurs if you open a new drawing with a
     relative path then attempt to save it using the SAVE command.

*24. There is a problem with any command which uses the new File
     Dialog box to allow for file selection.  When you change the
     file search pattern so that it matches enough file names to
     require the slider bar to be used then slide the bar to the
     bottom of this list it jumps back to the top of the list.  To
     see this, load a drawing with enough blocks to enable the
     sliders in a list box.  Call DDINSERT and pick Block to get a
     listing of the blocks.  Change the Pattern specification to
     anything that will retain the sliders (or just delete the "*"
     and enter it again).  Then slide the list to the bottom and
     release - it goes back to the top of the list.  It happens
     whenever you change the Pattern specification.  However, it
     will work correctly if you do it a second time - only happens
     the first time after changing the Pattern specification.  This
     problem occurs in every command which utilizes the R12 file
     dialog box.

 25. The variable XREFCTL is ignored by the OPEN command. 
     Regardless of the setting of XREFCTL, an .XLG file will be
     created when you open an existing drawing which already
     contains Xrefs.  No known workaround.

 26. With file locking enabled and FILEDIA=0, if you shell out of
     ACAD and delete the MNX file for the current menu then return
     to the editor and run the MENU command, you get:
         "FATAL ERROR: MENU1 1"

     The reason for the error is that ACAD keeps the .MNX file
     open, and when you run the menu command ACAD is trying to
     close a file which no longer exists.  The reason for deleting
     the .MNX file was to force ACAD to recompile the .MNU which
     had been edited on a different machine and was newer, but had
     a date older than the .MNX file.  The workaround is to change
     to a different menu, then shell out and delete the .MNX of the
     original menu, then change back to the original menu.

 27. There is a bug in the implementation of the alternate-font-
     prompt-reduction (AFPR) mechanism.  AFPR is a new feature in
     R12 which is supposed to cut down on the number of prompts for
     "Can't find font 'XXX'" when you open a drawing by
     substituting the font you specify for the first missing font
     for each remaining style in the drawing which uses the same
     font.  Turns out that AFPR is case-sensitive, so if the first
     font was really entered as "helv", then it won't match the
     next one if it was entered as "HELV".  No known workaround.

 28. Here is another problem with the DLDMODES command in R12. 
     Start a new drawing, make a layer called ZEBRA, then run the
     DLDMODES command.  Set the filter for the layer names to "Z*". 
     Pick to select the ZEBRA layer, then rename it to MYZEBRA.  At
     this point ACAD displays a message that no more layers match
     the specified filter, then places a string of garbage
     characters in both the layer name field and the current layer
     field of the dialog box.  ACAD appears to be having problems
     when the last layer of a filtered display is removed from the
     list.  Select OK, then immediately run the DDLMODES command
     again.  On large drawings, this sequence is generating a
     "FATAL ERROR: NULL pointer referenced" about 20-30% of the
     time.  No known workaround.

 29. If you specify an old ACAD .MNU/.MNX file for the current menu
     name and there is a matching .MNL file in the ACAD path, the
     next time you run the menu command you will generate a fatal
     "HEAP MANAGEMENT Error #6" and get dumped instantly to the DOS
     prompt.  Because your menu is named ACAD.MNX, AutoCAD finds
     and loads the ACAD.MNL AutoLISP file, which in turn loads
     ACADR12.LSP.  Well, ACADR12.LSP contains (menucmd "Pn.i")
     calls to gray-out certain menu items (which makes little sense
     for your menu, since its structure is different). Anyhow, the
     problem appears to be due to those (menucmd) calls being for
     items beyond what your menu defines.  The only workaround is
     to call your menu something other than ACAD.MNX.

 30. The new variable PICKAUTO does not work.  Regardless of its
     setting, ACAD allows you to draw a selection window (both
     window and crossing window) automatically at the "Select
     objects: " prompt.  Setting PICKAUTO to 0 is supposed to
     disable this automatic windowing, but it doesn't.

 31. There's a bug in the POSTSCRIPT sampleprolog. If you included
     the code-handling for linetypes, there's a line that refers to
     "acad-ltype-known", and another that refers to "acad-linetype-
     known". They should both be the same; if not, your printout
     will probably fail silently.  In acad.psf, globally change
     acad-ltype-known to acad-linetype-known.

*32. With certain Sparcstation configurations, the R12 DDEDIT
     command will crash ACAD when you hit the <Return> key to
     finish editing. The only workarounds are to use the change
     command to modify the text instead of DDEDIT, or to use the
     system mouse to click on the OK box.

*33. If any portion of a block is visible within the graphics
     window it is included in a "window" selection set if the
     insertion point of the block is outside the graphics window. 
     No known workaround.  It turns out that this is not a bug and
     is performing as documented under the "Window Selection"
     command of the ARM.

 34. After restoring a PCP file which has a default plot file name
     which contains a path, any PCP files saved (during the same
     editing session) will contain the default plot file name with
     path that was originally read in, instead of the current
     default plot file name.

 35. When saving a PCP file, if the current time is less than 10
     minutes past the hour, the leading 0 of the minutes in the
     time field of the PCP is dropped, i.e. 3:05pm is written as
     15:5 instead of 15:05.

 36. The TRIM command is not properly handling PLINES during a trim
     operation.  To show this, draw two vertical lines, then draw
     a pline which crosses both lines.  Run the TRIM command and
     select the two vertical lines as the cutting edges, then trim
     the left side of the Pline hanging outside the left line and
     then the part hanging outside the right side.  Finally select
     the remaining pline section between the two lines.  You have
     now in effect trimmed the entire pline.  No known workaround.

 37. When rendering using SVADI in dual screen mode, the Render
     option places garbage on the >graphic display< (note: ACAD
     menu still visible) in 1024x768x256. Turning off dual screen
     corrects the problem. 

*38. Configuring for a binary plotter file with 1 pen causes
     AutoCAD to ask a nonsensical question, viz., "How many pens?". 
     Also, the description for both the "AutoCAD file output
     formats" and "ADI plotter or printer" choices says "pre 4.1". 
     
 39. The DDEDIT command is supposed to accept 256 characters, but
     it only accepts 255 it only returns 254 characters.

*40. On some systems AutoCAD will dump straight to DOS without a
     warning when you run the DXFIN command with FILEDIA=1 and
     enter the name of the file direct from A: with no floppy in
     the drive and answer "F" to the resulting "Retry, Fail:"
     prompt.  The same thing happens with OPEN, (getfiled) and
     INSERT A:XXX.  Same thing with drive B:, too.  This problem
     seems to be caused by the floppy drive not being able to
     detect whether the drive door has been opened (change-line
     support).

 41. In LISP, passing a "nil" instead of a 2D point to the
     new_dialog command generates a "FATAL ERROR: NULL POINTER
     REFERENCED".  The following code demonstrates the problem:

          (setq di_dcl_id (load_dialog "dlgtest.dcl"))
          (new_dialog "dimensions" di_dcl_id "" nil)

 42. With file locking enabled and FILEDIA=1, save the current
     file, make some changes, then shell out of ACAD and delete the
     .DWK file.  Now end out of ACAD.  You get an alert box stating
     that ACAD was unable to lock the current drawing.  Select OK
     and the same alert box reappears.  Select OK a second time and
     you are returned to the DOS prompt as expected.  Do a
     directory of the file you were editing and you will see that
     there is a .BAK file and a 0 byte .DWK file, but no drawing
     file.  Any changes since your last save have been lost.  The
     same problem occurs if FILEDIA=0, except when you end there is
     no alert box displayed and ACAD appears to hang, but it is
     really waiting for you to hit "RETURN" to acknowledge the
     message in the alert box (which isn't visible).  The work
     around is to either not delete the .DWK file while editing the
     drawing, or disable file locking in the configuration menu if
     file locking is not needed.

 43. The DDCHPROPS command will not allow you to change an entity
     to a locked layer while both the CHANGE and CHPROP commands
     will.

 44. There is a problem with the hatch angle recorded and reported
     by BHATCH.  Draw a rectangle and rotate it 25 degrees. Then
     adjusted the UCS by using the UCS Entity Command. Hatched the
     rectangle and the angle displayed is 25 degrees. After
     applying the pattern and attempting to hatch again the angle
     displayed was 50 degrees.  Apply it and hatch again and it
     reads 75 degrees. 

*45. The lisp expression (ssget "X" (list (cons 0 "INSERT") (cons
     -4 "=,=,=") (cons 10 (list 0 0 z)))) doesn't work.  The z
     coordinate isn't being evaluated in the relational test with
     blocks.

*46. Documentation bug.  The ACAD Reference Manual index is missing
     references to these AutoCAD commands: GraphScr, TextScr,
     Redefine, Undefine, Script, RScript and Resume.

*47. Documentation bug.  The ADS Reference Manual example on page
     108 which shows how to use ads_entmake() to generate a
     polyline is incomplete.  The codes for the linetype and color
     were omitted for each VERTEX and for the SEQEND.  If the
     linetype and color are not included in the ads_buildlist()
     command for these items, the AUDIT command will report several
     errors in the drawing after running the example as shown.

*48. When plotting using MM units, if you specify any paper size
     other than MAX, the resultant plotted dimensions were 25.4
     times smaller than specified.  The workaround is to either
     specify MAX for the paper size, or multiple the desired paper
     size by 25.4 (e.g. 841,594 becomes 21361.4,15087.6) when
     entering the size.

*49. Create a visible attribute on layer 0.  Create a block called
     TEST which consists solely of the attribute you just defined. 
     Make a new layer called HOWCOME and insert the TEST block onto
     this layer and enter "THIS IS TEXT" at the attribute value
     prompt.  Freeze layer 0.  The attribute value of "THIS IS
     TEXT" is still visible on the screen, as it should be since
     anything created on Layer 0 is supposed to take on the
     properties of the insertion layer.  Now try to select the
     block using any command, including DDATTE, ERASE, MOVE, COPY,
     etc. and you will not be able to.  The only known workaround
     is to THAW Layer 0.

*50. When plotting from Paperspace, filled entities (i.e. arrow
     heads, fat polylines, solids, etc.) contained within an XREF
     but are on a layer which is frozen using VPLAYER, show up in
     the plot preview and also in the actual plot.  The following
     script demonstrates the problem.
          layer
          m
          solids
          
          solid
          5,5
          10,5
          7,10
          
          
          saveas
          DWG1
          new
          DWG2=
          xref
          attach
          DWG1
          0,0
          
          
          
          tilemode
          0
          mview
          0,0
          15,15
          zoom
          ext
          vplayer
          freeze
          *solid*
          All
          
     At this point, if you do a full plot preview, the solid is
     displayed even though the layer has been frozen.  The only
     workaround is to freeze the layer in the original drawing
     instead of using VPLAYER in the drawing which contains the
     XREF.
