screen(HW)

Description

The system console device can be either a terminal(a serial adapter device,tty1a) or a systemkeyboard display adapter monitor (tty01).

/dev/console is the device used by the systemadministrator for system maintenance (single-user) operations.It is thetty to which the first default shell is attached.

System error messages from the kernel are written to/dev/console, which is normally the currentmultiscreen. If/dev/console is the defaultoutput device for system error messages, and the displaybeing used is switched to graphics mode, console messagesare not displayed.

When the video device returns to text mode, a noticemessage is displayed and the text of the kernel error canbe recovered from/usr/adm/messages.

Initially,/dev/consoleis linked to/dev/systty.The actual physical device accessed via/dev/systtyis selected during boot,and is typically the device used to control the bootup procedure.The default physical device/dev/systtyis determined byboot(HW)when the system is brought up.

/dev/syscon is the system console device used byinit.Seeinit(M)for more information.

Although alltty[01-n]devices may be open concurrently, only one of thecorresponding devices can be active at any given time. Theactive device displays its own screen and takes solepossession of the keyboard. It is an error to attempt toaccess thecolor,monochrome,ega, orvgafile when no corresponding adapter exists or nomultiscreens are associated with it.

To get to the next consecutive console screen, enter<Ctrl><PrtSc>. Any active screen may be selected byentering <Alt><Fn> (or <Ctrl><Alt><Fn>when running in a graphical environment), where<Fn> is one of the function keys.For example, <F1> refers to thetty01 device.

Code examples are included in the section ``Examples'' inscreen(HW)to help programmersuse theioctl(S)calls documented here.

Control modes

SWAPCGA

Selects the regular color display as the output device for the multiscreen.

SWAPEGA

Selects the enhanced color display as the output device for the multiscreen.

SWAPMONO

Selects the monochrome display as the output device for the multiscreen.

SWAPVGA

Selects the video graphics array color display as theoutput device for the multiscreen.

CONS_CURRENT

Returns the display adapter type currently associated with the multiscreen.The return value can be one of:MONO,CGA,EGA,orVGA.

Changing the VGA color map

For example, the red, green, and blue intensities for thenth color map entry are represented by the valuesof the array membersn3,n3+1, andn3+2 respectively.

The argumentarg toioctl should point to anarray of 192 unsigned characters. This array may be used to readthe existing color map, or to set a new color map.

VGA_GETPALLET

Read the existing color map entries into the array pointedto byarg.

VGA_SETPALLET

Set new color map entries read from the array pointed tobyarg.

Display modes

SW_B80x25

Selects 80x25 black and white text display mode.(MONO, CGA, EGA, VGA)

SW_C80x25

Selects 80x25 color text display mode.(CGA, EGA, VGA)

SW_B40x25

Selects 40x25 black and white text display mode.(MONO, CGA, EGA, VGA)

SW_C40x25

Selects 40x25 color text display mode.(CGA, EGA, VGA)

SW_BG320

Selects 320x200 black and white graphics display mode.(CGA, EGA, VGA)

SW_CG320

Selects 320x200 color graphics display mode.(CGA, EGA, VGA)

SW_BG640

Selects 640x200 black and white graphics display mode.(CGA, EGA, VGA)

SW_EGAMONO80x25

Selects EGA (Enhanced Graphics Adapter) mode 7 -- emulatessupport provided by the monochrome display.(EGA, VGA)

SW_EGAMONOAPA

Selects EGA support for 640x350 graphics display mode(EGA mode F, EGA with mono monitor)

SW_ENH_MONOAPA2

Selects EGA mode F*.(EGA with mono monitor)

SW_ENHB40x25

Selects enhanced EGA support for 40x25 black and white textdisplay mode.(EGA, VGA)

SW_ENHC40x25

Selects enhanced EGA support for the 40x25 color text displaymode.(EGA, VGA)

SW_ENHB80x25

Selects enhanced EGA support for 80x25 black and white textdisplay mode.(EGA, VGA)

SW_ENHC80x25

Selects enhanced EGA support for 80x25 color text display mode.(EGA, VGA)

SW_ENHB80x43

Selects enhanced EGA support for 80x43 black and white textdisplay mode.(EGA, VGA)

SW_ENHC80x43

Selects enhanced EGA support for 80x43 color text display mode.(EGA, VGA)

SW_CG320_D

Selects EGA support for 320x200 graphics display mode(EGA mode D).(EGA, VGA)

SW_CG640_E

Selects EGA support for 640x200 graphics display mode(EGA mode E).(EGA, VGA)

SW_CG640x350

Selects EGA support for 640x350 graphics display mode(EGA mode 10).(EGA, VGA)

SW_ENH_CG640

Selects EGA mode 10*.(EGA, VGA)

SW_MCAMODE

Reinitializes the monochrome adapter.(MONO)

SW_VGA40x25

Selects VGA support for the 40x25 color text display mode(VGA mode 1+).

SW_VGA80x25

Selects VGA support for the 80x25 black and white text display mode(VGA mode 2+).

SW_VGAM80x25

Selects VGA mode 7+ -- emulatessupport provided by the monochrome display.(VGA with mono monitor)

SW_VGA11

Selects VGA support for the 640x480 graphics display mode(VGA mode 11).

SW_VGA12

Selects VGA support for the 640x480 graphics display mode(VGA mode 12).

SW_VGA13

Selects VGA support for the 320x200 graphics display mode(VGA mode 13).

Getting display modes

CONS_GET

Returns the current display mode setting for current displayadapter.(All)

CGA_GET

Returns the current display mode setting of the color graphics adapter.(CGA only)

EGA_GET

Returns the current display mode setting of the enhanced graphics adapter.(EGA only)

MCA_GET

Returns the current display mode setting of the monochrome adapter.(MONO only)

VGA_GET

Returns the current display mode of the video graphics adapters.(VGA only)

CONS_GETINFO

Returns structurevid_info.Size of structure (first field) must be filled in by user.

struct vid_info{  short  size;           /* must be first field          */  short  m_num;          /* multiscreen number, 0 based  */  ushort mv_row, mv_col; /* cursor position              */  ushort mv_rsz, mv_csz; /* text screen size             */  struct colors mv_norm, /* normal attributes            */                mv_rev,  /* reverse video attributes     */                mv_grfc; /* graphic character attributes */  uchar_t mv_ovscan;     /* border color                 */  uchar_t mk_keylock;    /* caps/num/scroll lock         */};

CONS_6845INFO

Returns structurem6845_info.Size of structure (first field) must be filled in by user.

struct m6845_info{  short   size;          /* must be first field        */  ushort  screen_top;    /* offset of screen in video  */  ushort  cursor_type;   /* cursor shape               */};

CONSADP

Returns the number of the current multiscreen displayed on theadapter specified by the value of the argumentarg toioctl. Possible adapter types areMONO, CGA, PGA, EGA, andVGA (definedin/usr/include/sys/comcrt.h).If no match is found,ioctl returns -1 anderrnois set toENXIO.

GIO_ATTR

Return value ofioctl is 6845-style attribute byte in effect.

GIO_COLOR

Return value ofioctl is 0 or 2 depending on whetherthe device supports color.

GIO_SCRNMAP

Gets the 256-byte screen map table, which is the mapping ofASCII values (0-255) onto the PC video ROMfont characters (0-255).Note that control characters (ASCII values less than hex 20)have control functions and do not display ROM characters (forexample, ^J is newline).

This is often used to map the low font valuesthat normally correspond to ASCII control values to higherASCII values, thus displaying the desired ROM characters.

PIO_SCRNMAP

Puts the 256-byte screen map table (seeGIO_SCRNMAP).

GIO_KEYMAP

Seekeyboard(HW).

GIO_FONT8Xn

Gets font, wheren is 8, 14, and 16.Argument is a pointer to a font table.Size of 8x8 font table is 8X256 bytes, 8x14 is 14X256 bytes, etc.

PIO_FONT8Xn

Puts font, wheren is 8, 14, and 16.Argument is a pointer to a font table.Size of 8x8 font table is 8X256 bytes, 8x14 is 14X256 bytes, etc.

Memory mapping modes

Note that theMAPioctls map the memory associated withthe current mode. You must put the adapter into the desiredmode before performing mapping, or the pointers returnedwill not be appropriate.Refer to your hardware manual for detailson various displays, adapters, and controllers.

Theseioctlrequests can be used to map the display memory:

MAPCGA

Maps the color adapter's display memory into the user's data space.(CGA only)

MAPCONS

Maps the display memory of the adapter currently being usedinto the user's data space.(All)

MAPEGA

Maps the enhanced graphics adapter's display memory into theuser's data space.(EGA only)

MAPMONO

Maps the monochrome adapter's display memory into the user's data space.(MONO only)

MAPVGA

Maps the video graphics adapter's display memory into theuser's data space.(VGA only)

   char *dp;   int retval;   .   .   .   /* fd is a file descriptor for a multiscreen device */   retval = ioctl (fd, MAPCONS,0L);   dp = (char *) retval;   .   .   .

1. Switch modes with anioctl.(The ``switch'' can be to the present mode.)See the``Display modes''section of this manual page.

2. Change the start address high and lowaddresses with the in-on-port/out-on-portioctl.

MAP_CLASS

Packageioctl that gives I/O privileges to an arbitrary listof ports and maps an arbitrary frame buffer into the user's addressspace identified by a string found in thestructvidclassvidclasslist[].For example:

char *ioctl(fd, MAP_CLASS, video_class_name)char *video_class_name;

This returns a pointer to the frame buffer. See/etc/conf/pack.d/cn/class.h for descriptions ofthe existing classes. Note that the link kitmustbe installed in order to find this file. (Theclass.h file is normally generated bymkdevgraphics.)

EGA_IOPRIVL
VGA_IOPRIVL

These add the list of I/Oports found on standard EGA and VGAcards into the process' TSS I/Opermission bitmap. This allows the process to access theEGA I/O ports directly from user spacewith 386IN andOUT instructions. (Seesample code under``Examples''.)I/O instructionsexecuted in this manner are slower thanI/O instructions executed when the I/Oprivilege level is raised to 3 (see instruction timings inIntel's80386 Programmer's Reference Manual).

A process' I/O privilege level can be set, allowing for thefaster execution of I/O instructions with thesysi86(S)subfunctionV86SC_IOPL:

sysi86 (SI86V86,V86SC_IOPL, 0x3000)

This sets the I/O privilege to 3 as described above. Only thesuperuser can do this.

KDDISPTYPE

This call returns display information to the user.The argument expected is the buffer addressof a structure of typekd_disparam into which displayinformation is returned to the user.Thekd_disparam structure is defined as follows:

struct kd_disparam       {          long type;    /* display type */          char *addr;   /* display memory address */       }

Possible values for thetype field include:

KD_MONO for the IBM monochrome display adapter
KD_HERCULES for the Hercules monochrome graphics adapter
KD_CGA for the IBM color graphics adapter
KD_EGA for the IBM enhanced graphics adapter
KD_VGA for the IBM video graphics adapter

KDDISPINFO

Returnsstruct kd_dispinfo, which contains adapter type and physicaladdress of frame buffer, as follows:

struct kd_dispinfo{char *vaddr;          /* memory address */paddr_t physaddr;     /* memory address */unsigned long size;   /* memory size */}

KIOCSOUND

Starts sound generation. Turns on sound. Thearg is theperiod of the bell tone in units of 840.3 nanoseconds. A value of 0 turns off the sound.This is useful for generating tones while in graphics mode.

KDGETLED

Gets keyboard LED status.The argument is a pointer to a character.The character will be filled with a Boolean combination of the followingvalues:

0x10Caps lock and Scroll lock are on
0x11Scroll lock and Num lock are on
0x04Scroll lock is on
0x02Num lock is on
0x01Caps lock is on

KDSETLED

Sets keyboard LED status. The argument is a character whose valueis the Boolean combination of the values listed under ``KDGETLED''.

KDMKTONE

(SeeKIOCSOUND.)The argument is a 32-bit value, with thelower 16 bits set to the frequency and the upper 16 bits set to theduration (in milliseconds).

KDSETMODE

Sets console in text or graphics mode.The argument is of type integer, which should contain one of thefollowing values:

KD_TEXT(sets console to text mode)
KD_GRAPHICS(sets console in graphics mode)

Note, the user is responsible for programming the color/graphics adapterregisters for the appropriate graphical state.

KDGETMODE

Gets current mode of console.Returns integer argument containing eitherKD_TEXT orKD_GRAPHICS as defined in theKDSETMODEioctldescription.

KDENABIO

Enable in's and out's to video adapter ports. No argument.

KDDISABIO

Disable in's and out's to video adapter ports. No argument.

KDGKBTYPE

Always returns 0.

KIOCINFO

Always returns 0x6B64.

VT_SETMODE

Sets the virtual terminal mode.The argument is a pointer to avt_modestructure.

VT_GETMODE

Determines what mode the active virtual terminal is currently in,eitherVT_AUTO orVT_PROCESS.The argument to theioctl is the address of thefollowing type of structure:

struct vt_mode {   char   mode;   /* VT mode */   char   waitv;  /* if !=0, vt hangs on writes when                     not active */   short  relsig; /* signal to use for release request */   short  acqsig; /* signal to use for display acquired */   short  frsig;  /* signal to use for forced release */   }
   #define VT_AUTO     0x00  /* automatic VT switching */   #define VT_PROCESS  0x01  /* process controls                                switching */

Thevt_mode structure will be filled in with the currentvalue for each field.

VT_RELDISP

Tells the virtual terminal manager whether the display hasbeen released by the process.

0 release refused
1 release acknowledged
2 acquire acknowledged

VT_ACTIVATE

Makes the multiscreen number specifiedin the argument the active multiscreen.The video driver will cause a switch to occur in the same manneras if a hotkey sequence had been typed at the keyboard.If the specified multiscreen is not open or does not exist,the call will fail anderrno will be set toEINVAL.

Graphics adapter port I/O

   struct port_io_arg {   struct port_io_struct args[4];   };

   struct port_io_struct {           char dir;    /* direction flag (in vs. out) */           unsigned short port;   /* port address */           char data;   /* byte of data */   };

If you are not using any of theport_io_structstructures, load theportwith 0, and leave the unused structures at the end of the array.Refer to hardware manuals for port addresses and functionsfor the various adapters.

You can use the followingioctl commands to input or outputa byte on the graphics adapter port:

CONSIO

Inputs or outputs a byte on the current graphics adapter port as specified.(All)

MCAIO

Inputs or outputs a byte on the monochrome adapter port as specified.(MONO only)

CGAIO

Inputs or outputs a byte on the color graphics adapter port as specified.(CGA only)

EGAIO

Inputs or outputs a byte on the enhanced graphics adapter port as specified.(EGA only)

VGAIO

Inputs or outputs a byte on the video graphics arrayadapter port as specified.(VGA only)

To output a byte, loaddirwithOUT_ON_PORT, loadportwith the port address of the graphics adapter, and loaddatawith the byte you want output to the graphics adapter port.

Function keys

   struct fkeyarg {      unsigned short keynum;      char keydef [MAXFK];      char flen;   }

SETLOCKLOCK

Toggles the <Caps Lock> and <Num Lock> keys to beeither global to all the multiscreens, or local to each individualmultiscreen. To make the <Caps Lock> global (its default), setthearg parameter to 1. To make the <Caps Lock> local toeach screen, set thearg parameter to 0.

See thescancode(HW)manual page for more function keyioctls.

SCOANSI terminal emulation

The definition of ``scoansi'' changed with SCO OpenServer Release 5.0.6.Earlier versions of SCO OpenServer supported most (but not all) of thesequences described here. Most applications should experience noproblems with the new functionality, but a backward compatibility modeis available for applications that rely on the previous behavior.

To enable backwards compatibility mode, runmkdev scoansiand select the option to use the new in-kernel scoansi emulator.You are then asked to relink the kernel and reboot the system.Seemkdev(ADM)for details.

SCOANSI screen attribute sequences

The console driver accepts both7-bit CSI sequences and 8-bit sequences.The 8-bit CSI sequencecollapses ``ESC ['' into a single 8-bit character,0x9b. Thus, ``ESC [ 2 J'' (0x1b-0x5b-0x32-0x4a) and ``CSI 2 J''(0x9b-0x32-0x4a) are equivalent.

In all of the sequences described here,if an argument is expected but omitted, adefault value of 1 is implied. For example, ``CSI 1 B'' and ``CSI B'' areequivalent. Where this is not the case, it is highlighted and describedin the text.

Beginning with SCO OpenServer Release 5.0.6(or earlier versions if youhave an updated console driver), the console driver now supports whatis known as ascrolling region, a virtual screen definedby the CSR control sequence. Any lines outside the defined marginsare not subject to scrolling, and under normal circumstances you cannotmove the cursor outside of the scrolling region. In effect, this reducesthe addressable size of the display (even though the physical screen maystill be at 80 columns and 25 rows). All cursor addressing sequences andscrolling is limited to the defined region. In this way, a scrollingregion is no different from a window that occupies the full screen.However, certain control sequences deal with absolute cursor positionand thus can violate the boundaries of the scrolling region.Care must be taken when using these absolute position controlsequences to avoid unexpected results.

Attributes

The attributes and modes used to display characters on the screen are knownas thegraphics rendition, and can be controlled by the SGR (``setgraphics rendition'') sequence described later.A set of SCO OpenServer specific control sequencescan be used to control individuals portionsof the graphics rendition. See-1for details.

``scoansi'' always uses four sets of graphics attributes:current, normal, reverse and graphics. The currentattribute is the attribute that is used when the screen is cleared, whennew lines are introduced as a result of scrolling the screen, or when newcharacters are drawn on the screen. The normal attribute is the fallbackattribute that is used when no attribute modifiers are active. The reverseattribute is used when reverse video mode is active, and the graphicsattribute is used when a graphics (or linedraw) character neeeds to bedisplayed. It is possible, although uncommon, for all of these attributesto be completely different. For example, it is possible for the normalattribute to be grey text on a black background, for graphics characters tobe displayed with a bright magenta foreground on a blue background, and forcharacters in reverse vide to be displayed as yellow text on a cyanbackground.

When you use the SGRor SCO OpenServer specific escape sequences to change attributes,you affect one or more of the attribute values.For example, setting the foreground color to redusing the SGR sequencesets the normal and graphics foreground colors to red,and the reverse video background to red.Using the SCO OpenServer specific escape sequences,you can set just the normal and graphics foreground colorwithout affecting the background color of the reverse video attribute.Once the color has been set,``scoansi'' selects the appropriate attribute value(either normal, reverse or graphics,depending on the attribute modifiersand the character to be drawn)and makes that the current attribute.This attribute is then used for drawing new charactersand when the screen is scrolledor a line or character is cleared.

It is possible to change the attributes that are used when new lines arecreated by a scroll, and the attributes used when characters are erasedfor any reason. The default behavior is to use the current attribute.However, it is possible to set a special terminal mode that will force thenormal attribute to be used. See-1for details.

Attributes are treated subtly differently if you enablebackwards compatibility mode.This mode handles attributes (and other semantics) asthe console driver did prior to SCO OpenServer Release 5.0.6.Where such differences exist, they are described for the graphicsrendition that is affected. To understand how these attributes areused, print the various escape sequences out andstudy the visual effect that they have.

Display Fonts

Font 1 can be used to display the actual glyphs as defined by the PC ROMBIOS. This font is used to display the so-called ``graphics'' characters,or linedraw characters. All characters are displayed withoutinterpretation.

Font 2 is used to display ROM BIOS characters as well, but with slightlydifferent rules. This font was invented in order to be able to displayupper ASCII characters (8-bit ASCII characters, or characters above0x7f). When using this font, all of the lower ASCII characters will havetheir glyphs displayed. For all other characters, if the high bit of thecharacter is set, this font will unset it and then display the resultingglyph. If, however, the high bit is not set, the this font will set it anddisplay the resulting glyph.

Font 3 is similar to font 2, except that the lower ASCII characters areprocessed as they are in font 0 (that is, they follow thesemantics described for``ASCII Control Sequences'').Any other character is displayed asin font 2. In other words, any character that has its high bit setwill have it unset by this font and the resulting glyph displayed, and anyinput character that does not have its high bit set will have it set by thefont, and the resulting glyph displayed.

For example, suppose that the character that was sent to the console wasthe character ``D''. In font 0, it would appear exactly like that, as a``D''. The same applies in font 1. In fonts 2 and 3 however, since thecharacter does not have its high bit set, the font will set it and thendisplay the resulting glyph. Thus, the character 0x44 is now displayed as0xc4, which is the character used to draw a single horizontal line.

If the character sent to the console was the actual character 0xc4, then inboth fonts 0 and 1, it would appear as the horizontal line drawcharacter. However, in fonts 2 and 3, because its high bit is set, thefont will remove it and then display the resulting glyph, which is thecharacter ``D''.

ASCII Control Sequences

ANSI screen control sequences

In the second form, where 3 or more parameters are specified, theparameters are the top, bottom, left and right margins respectively.If you omit the last parameter, the extreme edge of the screen isassumed to be the right margin.

If any of the parameters are out of bounds, they are clipped. If any ofthe parameters would cause an overlap (i.e. the bottom margin is higherthan the top margin, or the right margin is less that the left margin),then this command is ignored and no scrolling region or window will beactive. If all of the parameters are correct, then the cursor is movedto the top left hand corner of the newly-created region. Thenew region will now define the bounds of all scroll and cursormotion operations.

Additional screen control sequences

Additional SCO OpenServer screen control sequences

ISO Color Map

Diagnostics

CONFIG: console: Cannot allocate SCRNMEM =nk (NSCRN =n too many screens)

WARNING: console: Kernel messages lost on non-text screen         Check kernel messages logfile

PANIC: console: Too many keyboard groups (MAXKBGRPS max)

Examples

Sample code (part 1 of 4)

#include <stdio.h>
#include <sys/types.h>#include <sys/signal.h>#include <sys/vtkd.h>
#define SIG_RELSIGUSR1#define SIG_ACQSIGUSR2
int Isdisplayed;/* flag: when are we flipped away */char *Screenmem;/* physical map to the video RAM  */int graf();/* Set everything up  */void grafend();/* Restore user's text mode  */void grafquit();/* Clean-up and exit  */void rel_screen(), acq_screen();int Oldmode;/* save mode of user shell screen */
/* * Set up the graphics multiscreen stuff and call another * routine to set up card. */graf(){struct vt_mode smode;
Isdisplayed = 1;/* *  Set up to catch the screen switch signals. */signal(SIG_REL, rel_screen);signal(SIG_ACQ, acq_screen);/* * Set up the data structure that asks the driver * to send you signals when the screens are switched. * mode == VT_PROCESS means send screen switch signals. * mode == VT_AUTO means turn off screen switch signals (regular mode). * relsig == the signal you want when the user switches away. * acqsig == the signal you want when the user switches back to you. */smode.mode = VT_PROCESS;smode.waitv = 0;/* not implemented, reserved */smode.relsig = SIG_REL;smode.acqsig = SIG_ACQ;smode.frsig  = SIGINT;/* not implemented, reserved */
if(-1 == ioctl(0, VT_SETMODE, &smode)){perror("screen switch signal ioctl VT_SETMODE");exit(1);}signal(SIGINT, grafquit);grafmode();}

Sample code (part 2 of 4)

/* * this is the signal handler for when the user screen flips * away from us. */voidrel_screen(){signal(SIG_REL, rel_screen);Isdisplayed = 0;ega_save();/* * Tell the video driver that you have saved your state * and it can now have the card to switch to the new screen. * The video driver waits (forever) for this ioctl before * it will complete the screen switch requested by the user. * If you don't make this ioctl the screen switcher will * be wedged until it gets one.  It is best to have a * small one line reldisp.c program to unwedge your screen * switcher when development programs screw up from time * to time. */ioctl(0, VT_RELDISP, VT_TRUE);}
/* * this is the signal handler for when the user screen flips * back to us. */voidacq_screen(){signal(SIG_ACQ, acq_screen);Isdisplayed = 1;ega_restore();/* * Tell the video driver that you have restored your state * and screen switching can now continue. */ioctl(0, VT_RELDISP, VT_ACKACQ);}
voidgrafquit(){grafend();exit(0);}

Sample code (3 of 4)

/* * restore text mode. */voidgrafend(){ioctl(0, MODESWITCH | Oldmode, (char *)0);}
grafmode(){int adapter, privlcmd;/* * Confirm that we are on a supported video adapter. */adapter = ioctl(0, CONS_CURRENT, (char *)0);if(EGA != adapter && VGA != adapter){puts("Stdin must be an EGA or VGA multiscreen");exit(0);}

Sample code (4 of 4)

/* * Save the user's current text mode so you * can restore it on exit. */Oldmode = ioctl(0, CONS_GET, (char *)0);/* * Get privilege to do direct INs and OUTs to the video card. */if(EGA == adapter)privlcmd = EGA_IOPRIVL;elseprivlcmd = VGA_IOPRIVL;if(-1 == ioctl(0, privlcmd, 1)){perror("I/O privilege denied");exit(1);}/* * Have the video driver reprogram the card for EGA 640x350 16 color mode. */ega_grafmode();/* * Map the video card's frame buffer into your address space. * This must be done after the mode switch command or you get * frame buffer address for the wrong mode mapped in. */Screenmem = (char *)ioctl(0, MAPCONS, (char *)0);}

Warning

Limitations

Files

/dev/console

tty to which first shell is attached, used for system maintenance

/dev/systty

system error messages display device, linkedinitially to/dev/console

/dev/syscon

system console device, linked to the tty from whichinit(M)was last invoked

/etc/ioctl.syscon

default consoleioctl(S)settings used byinit(M)

/dev/tty[02-n]

provide character I/O between keyboard and monitor

/dev/color

/dev/monochrome

/dev/ega

/dev/vga

/etc/conf/pack.d/cn/class.h

list of existing video classes, generated bymkdev graphics

/usr/include/sys/vtkd.h

/usr/include/sys/comcrt.h

adapter types for console multiscreens

/usr/include/sys/console.h

/usr/include/sys/keyboard.h

See also

``System console bootstring'' in theSCO OpenServer Handbook

``Configuring video adapters'' inConfiguring Video Adapters

``Setting up serial consoles'' in theSCO OpenServer Handbook