**CIGAL Reference Manual, Chapter 1 (Topics): internals**
===== Internals -- Internal Variables =====
The following is a brief summary of the internal variables CIGAL uses to control various aspects of its operation. These variables are described in chapter 4 of the CIGAL User's Manual (see [[jvs:cigal:manual:chapter4:aflags|AFLAGS(4)]]).

In this table, the TYPE entry indicates the data type for each variable:
Number (N), Character String (S), String List (SL), Array (A),
Matrix (M), Image (I), Vector (V), Vector List (VL), Pointer (P)

|      NAME    |   TYPE |MEANING|
|      ====    |   ==== |=======|
|      aflags  |     N  |Flag controlling arithmetic options|
|      barleng |     N  |Default length of SKETCH calibration bar|
|      bitmask |     N  |not used|
|      boxval  |        | |
|      calbar  |     N  |not used|
|      calfact |        | |
|      camera  |     N  |Camera select for image processor digitizer|
|      cgain   |     N  |Image processor camera gain|
|      chkkey  |        | |
|      cmdlin  |     S  |DOS arguments to CIGAL when the program was started|
|      coffset |     N  |Image processor camera offset|
|      com1    |        | |
|      com2    |        | |
|      cpuspeed|     N  |CPU processing speed in MHz (approx.)|
|      ctrap   |     S  |Command string to be executed upon <Control>-C|
|      cursor  |     N  |Flag controlling cursor options|
|      cursval |     N  |not used|
|      cursx   |     N  |Current X postition of cursor|
|      cursy   |     N  |Current Y postition of cursor|
|      dac0    |     N  |Value of 1st D/A converter if present|
|      dac1    |     N  |Value of 2nd D/A converter if present|
|      datadir |     S  |Template for names of numbered file variables|
|      debug   |     N  |Flag controlling debugging options|
|      drawkeys|     S  | |
|      editor  |     S  |Name of file editor to use with ED command|
|      emembase|        | |
|      ememsize|        | |
|      flags   |     N  |Flag controlling runtime options|
|      fmenu   |   SL   |Srings defining Function keys and mouse buttons|
|      freestack|    N  |Amount of free stack remaining|
|      getx    |     N  |Get new X postition of cursor|
|      gety    |     N  |Get new Y postition of cursor|
|      gflags  |     N  |Flag controlling graphics options|
|      gplane  |     N  |Current graphics memory plane|
|      gunit   |        | |
|      hdrtxt  |     S  |Text stored in header block of file variables|
|      helpfile|     S  |Name of CIGAL help file (includes error messages)|
|      ibase   |     N  |Default base for numerical input (usually 10)|
|      iflags  |     N  |Flag controlling image processor options|
|      iplane  |     N  |Current image processor memory plane|
|      keybd   |     N  |Get a character from the keyboard|
|      lastvec |     N  |Highest vector number created in VECS|
|      lcolor  |     N  |Line color value for drawing vectors|
|      lpat    |     N  |Line pattern value for drawing vectors (not used)|
|      lwidth  |     N  |Line width value for drawing vectors (has bugs)|
|      margsize|     N  |Width of graphics screen including menu margin|
|      menufile|     S  | |
|      menuflag|     N  |Flag controlling which screen menu is active|
|      nargs   |     N  |Number of arguments for current macro program|
|      nmenus  |        | |
|      nvecs   |    N   |Number of active vectors in VECS|
|      nvdata  |        | |
|      obase   |     N  |Number base for TYPE output (usually 10)|
|      outlun  |     N  |Unit number for standard output (1 = CRT screen)|
|      path    |     S  |List of directories to search for macros and menus|
|      penwidth|     N  |How many drawn lines per vector line (usually 1)|
|      prompt  |     S  |Current command prompt message|
|      prpage  |     N  |Number of pages per printer page|
|      quitstr |     S  |Command string to be executed when quitting CIGAL|
|      sflags  |     N  |Flag controlling SKETCH options|
|      simage  |     P  | |
|      stack   |     A  |LONG array for direct access to internal stack|
|      state   |     N  |Flag indicating current execution state|
|      sysdir  |     S  |Name of CIGAL system directory|
|      tablet  |     N  |Flag controlling digitizing tablet options|
|      unit    |     N  |Current active device|
|      vdata   |     P  | |
|      vdatfil |     S  | |
|      version |     N  |Current CIGAL version number|
|      vec0    |        | |
|      vecfil  |     S  |Name of temporary file used for VECS|
|      vecs    |     P  |Pointer to a file vector list (VL) containing the list of active display vectors|
|      vimage  |     P  |Pointer to matrix or image variable in which to draw active graphics vectors|
|      vmode   |     N  |Current video mode|
|      vpage   |        | |
|      vplane  |     N  |Current video plane|
|      vwindow |        | |
|      xmarg   |     N  |Width of graphics menu margin|
|      zimage  |     P  |Pointer to matrix or image variable in which to draw depth map (Z-values) of active graphics vectors|
|     zvalue   |    N   |Default Z value for creating vectors||

**See Also:**\\
[[jvs:cigal|CIGAL Home]], 
[[jvs:cigal:manual|CIGAL Manual]], 
[[jvs:cigal:manual:chapter1|Topics List]], 
[[jvs:cigal:manual:help|Manual Help]]