dxf12.htm

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header section
--------------
the header section of the dxf file contains settings of variables 
associated with the drawing. these variables are set with various 
commands and are the type of information displayed by the status 
command. each variable is specified in the header section by a 9 
group giving the variable's name, followed by groups that supply the 
variable's value. the following list shows the header variables and 
their meanings.</pre>
    <pre>although this list is very similar to the list of system variables 
in appendix a of this manual, the two lists are not identical. be 
sure you're referring to the proper list.</pre>
    <pre>note: $axismode and $axisunit are no longer functional in release 
12.</pre>
    <pre>table 11-3. dxf system variables
+===============================================================+
| variable       | type   | description                         |
|----------------|--------|-------------------------------------|
| $acadver       | 1      | the autocad drawing database        |
|                |        | version number; ac1006 = r10,       |
|                |        | ac1009 = r11 and r12                |
|----------------|--------|-------------------------------------|
| $angbase       | 50     | angle 0 direction                   |
|----------------|--------|-------------------------------------|
| $angdir        | 70     | 1 = clockwise angles, 0 =           |
|                |        | counterclockwise                    |
|----------------|--------|-------------------------------------|
| $attdia        | 70     | attribute entry dialogs, 1 = on,    |
|                |        | 0 = off                             |
|----------------|--------|-------------------------------------|
| $attmode       | 70     | attribute visibility: 0 = none,     |
|                |        | 1 = normal, 2 = all                 |
|----------------|--------|-------------------------------------|
| $attreq        | 70     | attribute prompting during insert,  |
|                |        | 1 = on, 0 = off                     |
|----------------|--------|-------------------------------------|
| $aunits        | 70     | units format for angles             |
|----------------|--------|-------------------------------------|
| $auprec        | 70     | units precision for angles          |
|----------------|--------|-------------------------------------|
| $axismode      | 70     | axis on if nonzero (not functional  |
|                |        | in release 12)                      |
|----------------|--------|-------------------------------------|
| $axisunit      | 10, 20 | axis x and y tick spacing           |
|                |        | (not functional in release 12)      |
|----------------|--------|-------------------------------------|
| $blipmode      | 70     | blip mode on if nonzero             |
|----------------|--------|-------------------------------------|
| $cecolor       | 62     | entity color number; 0 = byblock,   |
|                |        | 256 = bylayer                       |
|----------------|--------|-------------------------------------|
| $celtype       | 6      | entity linetype name, or byblock    |
|                |        | or bylayer                          |
|----------------|--------|-------------------------------------|
| $chamfera      | 40     | first chamfer distance              |
|----------------|--------|-------------------------------------|
| $chamferb      | 40     | second chamfer distance             |
|----------------|--------|-------------------------------------|
| $clayer        | 8      | current layer name                  |
|----------------|--------|-------------------------------------|
| $coords        | 70     | 0 = static coordinate display,      |
|                |        | 1 = continuous update, 2 = &quot;d&lt;a&quot;    |
|                |        | format                              |
|----------------|--------|-------------------------------------|
| $dimalt        | 70     | alternate unit dimensioning         |
|                |        | performed if nonzero                |
|----------------|--------|-------------------------------------|
| $dimaltd       | 70     | alternate unit decimal places       |
|----------------|--------|-------------------------------------|
| $dimaltf       | 40     | alternate unit scale factor         |
|----------------|--------|-------------------------------------|
| $dimapost      | 1      | alternate dimensioning suffix       |
|----------------|--------|-------------------------------------|
| $dimaso        | 70     | 1 = create associative dimensioning,|
|                |        | 0 = draw individual entities        |
|----------------|--------|-------------------------------------|
| $dimasz        | 40     | dimensioning arrow size             |
|----------------|--------|-------------------------------------|
| $dimblk        | 2      | arrow block name                    |
|----------------|--------|-------------------------------------|
| $dimblk1       | 1      | first arrow block name              |
|----------------|--------|-------------------------------------|
| $dimblk2       | 1      | second arrow block name             |
|----------------|--------|-------------------------------------|
| $dimcen        | 40     | size of center mark/lines           |
|----------------|--------|-------------------------------------|
| $dimclrd       | 70     | dimension line color, range is      |
|                |        | 0 = byblock, 256 = bylayer          |
|----------------|--------|-------------------------------------|
| $dimclre       | 70     | dimension extension line color,     |
|                |        | range is 0 = byblock, 256 = bylayer |
|----------------|--------|-------------------------------------|
| $dimclrt       | 70     | dimension text color, range is      |
|                |        | 0 = byblock, 256 = bylayer          |
|----------------|--------|-------------------------------------|
| $dimdle        | 40     | dimension line extension            |
|----------------|--------|-------------------------------------|
| $dimdli        | 40     | dimension line increment            |
|----------------|--------|-------------------------------------|
| $dimexe        | 40     | extension line extension            |
|----------------|--------|-------------------------------------|
| $dimexo        | 40     | extension line offset               |
|----------------|--------|-------------------------------------|
| $dimgap        | 40     | dimension line gap                  |
|----------------|--------|-------------------------------------|
| $dimlfac       | 40     | linear measurements scale factor    |
|----------------|--------|-------------------------------------|
| $dimlim        | 70     | dimension limits generated if       |
|                |        | nonzero                             |
|----------------|--------|-------------------------------------|
| $dimpost       | 1      | general dimensioning suffix         |
|----------------|--------|-------------------------------------|
| $dimrnd        | 40     | rounding value for dimension        |
|                |        | distances                           |
|----------------|--------|-------------------------------------|
| $dimsah        | 70     | use separate arrow blocks if nonzero|
|----------------|--------|-------------------------------------|
| $dimscale      | 40     | overall dimensioning scale factor   |
|----------------|--------|-------------------------------------|
| $dimse1        | 70     | first extension line suppressed     |
|                |        | if nonzero                          |
|----------------|--------|-------------------------------------|
| $dimse2        | 70     | second extension line suppressed    |
|                |        | if nonzero                          |
|----------------|--------|-------------------------------------|
| $dimsho        | 70     | 1 = recompute dimensions while      |
|                |        | dragging, 0 = drag original image   |
|----------------|--------|-------------------------------------|
| $dimsoxd       | 70     | suppress outside-extensions         |
|                |        | dimension lines if nonzero          |
|----------------|--------|-------------------------------------|
| $dimstyle      | 2      | dimension style name                |
|----------------|--------|-------------------------------------|
| $dimtad        | 70     | text above dimension line if nonzero|
|----------------|--------|-------------------------------------|
| $dimtfac       | 40     | dimension tolerance display scale   |
|                |        | factor                              |
|----------------|--------|-------------------------------------|
| $dimtih        | 70     | text inside horizontal if nonzero   |
|----------------|--------|-------------------------------------|
| $dimtix        | 70     | force text inside extensions if     |
|                |        | nonzero                             |
|----------------|--------|-------------------------------------|
| $dimtm         | 40     | minus tolerance                     |
|----------------|--------|-------------------------------------|
| $dimtofl       | 70     | if text outside extensions, force   |
|                |        | line extensions between extensions  |
|                |        | if nonzero                          |
|----------------|--------|-------------------------------------|
| $dimtoh        | 70     | text outside horizontal if nonzero  |
|----------------|--------|-------------------------------------|
| $dimtol        | 70     | dimension tolerances generated if   |
|                |        | nonzero                             |
|----------------|--------|-------------------------------------|
| $dimtp         | 40     | plus tolerance                      |
|----------------|--------|-------------------------------------|
| $dimtsz        | 40     | dimensioning tick size: 0 = no ticks|
|----------------|--------|-------------------------------------|
| $dimtvp        | 40     | text vertical position              |
|----------------|--------|-------------------------------------|
| $dimtxt        | 40     | dimensioning text height            |
|----------------|--------|-------------------------------------|
| $dimzin        | 70     | zero suppression for &quot;feet &amp; inch&quot;  |
|                |        | dimensions                          |
|----------------|--------|-------------------------------------|
| $dwgcodepage   | 70     | drawing code page. set to the       |
|                |        | system code page when a new drawing |
|                |        | is created, but not otherwise       |
|                |        | maintained by autocad               |
|----------------|--------|-------------------------------------|
| $dragmode      | 70     | 0 = off, 1 = on, 2 = auto           |
|----------------|--------|-------------------------------------|
| $elevation     | 40     | current elevation set by elev       |
|                |        | command                             |
|----------------|--------|-------------------------------------|
| $extmax        | 10, 20,| x, y, and z drawing extents         |
|                | 30     | upper-right corner (in wcs)         |
|----------------|--------|-------------------------------------|
| $extmin        | 10, 20,| x, y, and z drawing extents         |
|                | 30     | lower-left corner (in wcs)          |
|----------------|--------|-------------------------------------|
| $filletrad     | 40     | fillet radius                       |
|----------------|--------|-------------------------------------|
| $fillmode      | 70     | fill mode on if nonzero             |
|----------------|--------|-------------------------------------|
| $handling      | 70     | handles enabled if nonzero          |
|----------------|--------|-------------------------------------|
| $handseed      | 5      | next available handle               |
|----------------|--------|-------------------------------------|
| $insbase       | 10, 20,| insertion base set by base command  |
|                | 30     | (in wcs)                            |
|----------------|--------|-------------------------------------|
| $limcheck      | 70     | nonzero if limits checking is on    |
|----------------|--------|-------------------------------------|
| $limmax        | 10, 20 | xy drawing limits upper-right       |
|                |        | corner (in wcs)                     |
|----------------|--------|-------------------------------------|
| $limmin        | 10, 20 | xy drawing limits lower-left        |
|                |        | corner (in wcs)                     |
|----------------|--------|-------------------------------------|
| $ltscale       | 40     | global linetype scale               |
|----------------|--------|-------------------------------------|
| $lunits        | 70     | units format for coordinates and    |
|                |        | distances                           |
|----------------|--------|-------------------------------------|
| $luprec        | 70     | units precision for coordinates     |
|                |        | and distances                       |
|----------------|--------|-------------------------------------|
| $maxactvp      | 70     | sets maximum number of viewports to |
|                |        | be regenerated                      |
|----------------|--------|-------------------------------------|
| $menu          | 1      | name of menu file                   |
|----------------|--------|-------------------------------------|
| $mirrtext      | 70     | mirror text if nonzero              |