screen(HW) 19 June 1992 screen(HW) Name screen - tty [01-n], color, monochrome, ega, vga display adapter and video monitor Description The tty [01-n] device files provide character I/O between the system and the video display monitor and keyboard. Each file corresponds to a separate teletype device. Although there is a maximum of 12 screens, the exact number available (n) depends upon the amount of memory in the com- puter. The screens are modeled after a 25-line, 80-column ASCII termi- nal, unless specified otherwise. System error messages from the kernel are written to /dev/console, which is normally the current multiscreen. If the /dev/console is the default output device for system error messages, and the display being used is switched to graphics mode, console messages are not displayed. When the video device returns to text mode, a notice message is displayed and the text of the kernel error can be recovered from usr/adm/messages. Although all tty[01-n] devices may be open concurrently, only one of the corresponding devices can be active at any given time. The active device displays its own screen and takes sole possession of the keyboard. It is an error to attempt to access the color, monochrome, ega, or vga file when no corresponding adapter exists or no multiscreens are associated with it. To get to the next consecutive screen, enter CtrlPrtSc. Any active screen may be selected by entering AltFn, where Fn is one of the function keys. For example, F1 refers to the tty01 device. Code examples are included in the section ``Examples'' to help program- mers use the ioctls documented here. Control modes Multiscreens can be reassigned to different adapters (in multi-adapter systems) with these ioctls : SWAPMONO Selects the monochrome display as the output device for the multiscreen. 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. SWAPVGA Selects the video graphics array color display as the output device for the multiscreen. To find out which display adapter type is currently attached to the mul- tiscreen, you can use ioctl(S) with the following request: CONSCURRENT Returns the display adapter type currently associated with the multiscreen. The return value can be one of: MONO, CGA, EGA, or VGA. Display modes The following ioctls can be used to change the video display mode: SWB80x25 Selects 80x25 black and white text display mode. (MONO, CGA, EGA, VGA) SWC80x25 Selects 80x25 color text display mode. (CGA, EGA, VGA) SWB40x25 Selects 40x25 black and white text display mode. (MONO, CGA, EGA, VGA) SWC40x25 Selects 40x25 color text display mode. (CGA, EGA, VGA) SWBG320 Selects 320x200 black and white graphics display mode. (CGA, EGA, VGA) SWCG320 Selects 320x200 color graphics display mode. (CGA, EGA, VGA) SWBG640 Selects 640x200 black and white graphics display mode. (CGA, EGA, VGA) SWEGAMONO80x25 Selects EGA (Enhanced Graphics Adapter) mode 7 - emu- lates support provided by the monochrome display. (EGA, VGA) SWEGAMONOAPA Selects EGA support for 640x350 graphics display mode EGA (mode F). (EGA with mono monitor) SWENHMONOAPA2 Selects EGA mode F*. (EGA with mono monitor) SWENHB40x25 Selects enhanced EGA support for 40x25 black and white text display mode. (EGA, VGA) SWENHC40x25 Selects enhanced EGA support for the 40x25 color text display mode. (EGA, VGA) SWENHB80x25 Selects enhanced EGA support for 80x25 black and white text display mode. (EGA, VGA) SWENHC80x25 Selects enhanced EGA support for 80x25 color text display mode. (EGA, VGA) SWENHB80x43 Selects enhanced EGA support for 80x43 black and white text display mode. (EGA, VGA) SWENHC80x43 Selects enhanced EGA support for 80x43 color text display mode. (EGA, VGA) SWCG320D Selects EGA support for 320x200 graphics display mode. (EGA mode D.) (EGA, VGA) SWCG640E Selects EGA support for 640x200 graphics display mode EGA (mode E). (EGA, VGA) SWCG640x350 Selects EGA support for 640x350 graphics display mode EGA (mode 10). (EGA, VGA) SWENHCG640 Selects EGA mode 10*. (EGA, VGA) SWMCAMODE Reinitializes the monochrome adapter. (MONO) SWVGA40x25 Selects VGA support for the 40x25 color text display mode (VGA mode 1+). (VGA) SWVGA80x25 Selects VGA support for the 80x25 black and white text display mode (VGA mode 2+). (VGA) SWVGAM80x25 Selects VGA mode 7+ - emulates support provided by the monochrome display. (VGA with mono monitor) SWVGA11 Selects VGA support for the 640x480 graphics display mode (VGA mode 11). (VGA) SWVGA12 Selects VGA support for the 640x480 graphics display mode (VGA mode 12). (VGA) SWVGA13 Selects VGA support for the 320x200 graphics display mode (VGA mode 13). (VGA) Switching to an invalid display mode for a display device will result in an error. Getting display modes The following ioctl( ) requests are provided to obtain information about the current display modes: CONSGET Returns the current display mode setting for current display adapter. (All) CGAGET Returns the current display mode setting of the color graphics adapter. (CGA only) EGAGET Returns the current display mode setting of the enhanced graphics adapter. (EGA only) MCAGET Returns the current display mode setting of the mono- chrome adapter. (MONO only) VGAGET Returns the current display mode of the video graphics adapters. (VGA only) CONSGETINFO Returns structure vidinfo (below). 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 */ }; CONS6845INFO Returns structure m6845info (below). Size of struc- ture (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 number of the multiscreen displayed on adaptor associated with that multiscreen. GIOATTR Return value of ioctl is 6845-style attribute byte in effect. GIOCOLOR Return value of ioctl is 0 or 2 depending on whether the device supports color. GIOSCRNMAP Gets the 256-byte screen map table, which is the map- ping of ASCII values (0-256) onto the PC video ROM font characters (0-256). Note that control characters (ASCII values less than hex 20) have control functions and do not display ROM characters (for example, ^J is new- line). This is often used to map the low font values that nor- mally correspond to ASCII control values to higher ASCII values, thus displaying the desired ROM charac- ters. PIOSCRNMAP Puts the 256-byte screen map table (see GIOSCRNMAP). GIOKEYMAP See keyboard(HW). GIOFONT8Xn Gets font, where n 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. PIOFONT8Xn Puts font, where n 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 The ioctl(S) routine is used to map the display memory of the various de- vices into the user's data space. Note that the MAP* ioctls map the memory associated with the current mode. You must put the adapter into the desired mode before performing mapping, or the pointers returned will not be appropriate. Refer to your hardware manual for details on various displays, adapters, and control- lers. These ioctl() requests can be used to map the display memory: MAPCONS Maps the display memory of the adapter currently being used into the user's data space. (All) MAPMONO Maps the monochrome adapter's display memory into the user's data space. (MONO only) MAPCGA Maps the color adapter's display memory into the user's data space. (CGA only) MAPEGA Maps the enhanced graphics adapter's display memory into the user's data space. (EGA only) MAPVGA Maps the video graphics adapter's display memory into the user's data space. (VGA only) For example, the following code can be used to acquire a pointer to the start of the user data space associated with the color graphics adapter display memory: char *dp; int retval; . . . /* fd is a file descriptor for a multiscreen device */ retval = ioctl (fd, MAPCONS,0L); dp = (char *) retval; . . . Note that when the display memory is mapped into the user space, the adapter's m6845 start address registers are not set. The start address can be reset in two ways, so that the start address of the display memory corresponds to the upper left hand corner of the screen: 1. Switch modes with an ioctl(). (The ``switch'' can be to the present mode). See the ``Display modes'' section of this manual page. 2. Change the start address high and low addresses with the in-on-port/out-on-port ioctl(). The in-on-port/out-on-port ioctl() can also be used to determine the current value in the start address register, and then set up a pointer to the offset in the mapped-in data space. MAPCLASS Package ioctl that gives I/O privileges to an arbitrary list of ports and maps an arbitrary frame buffer into the user's address space identified by a string found in the struct vidclass vidclasslist[]. 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 of the existing classes. Note that the link kit must be installed in order to find this file. (The class.h file is normally generated by mkdev graphics.) EGAIOPRIVL VGAIOPRIVL These add the list of I/O ports found on standard EGA and VGA cards into the process' TSS I/O permission bit- map. This allows the process to access the EGA I/O ports directly from user space with 386 IN and OUT instructions. (See sample code under ``Examples''.) I/O instructions executed in this manner are somewhat slower than I/O instructions executed when the I/O privilege level is raised to 3 (see instruction timings in Intel's 80386 Programmer's Reference Manual.) A process' I/O privilege level can be set, allowing for the faster execution of I/O instructions with the sysi86() subfunction V86SCIOPL: sysi86 (SI86V86, V86SCIOPL, 0x3000) This sets the I/O privilege to 3 as described above. Only the super user can do this. KDDISPTYPE This call returns display information to the user. The argument expected is the buffer address of a structure of type kddisparam into which display information is returned to the user. The kddisparam structure is defined as follows: struct kd_disparam { long type; /* display type */ char *addr; /* display memory address */ } Possible values for the type field include: KDMONO for the IBM monochrome display adapter KDHERCULES for the Hercules monochrome graphics adapter KDCGA for the IBM color graphics adapter KDEGA for the IBM enhanced graphics adapter KDVGA for the IBM video graphics adapter KDDISPINFO Returns struct kddispinfo, which contains adapter type and physical address 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. The arg is the period 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 following values: 0x10 Caps lock and Scroll lock are on 0x11 Scroll lock and Num lock are on 0x04 Scroll lock is on 0x02 Num lock is on 0x01 Caps lock is on KDSETLED Sets keyboard LED status. The argument is a character whose value is the Boolean combination of the values listed under ``KDGETLED''. KDMKTONE (See KIOCSOUND.) The argument is a 32 bit value, with the lower 16 bits set to the frequency and the upper 16 bits set to the duration (in milliseconds). KDSETMODE Sets console in text or graphics mode. The argument is of type integer, which should contain one of the fol- lowing values: KDTEXT (sets console to text mode) KDGRAPHICS (sets console in graphics mode) Note, the user is responsible for programming the color/graphics adapter registers for the appropriate graphical state. KDGETMODE Gets current mode of console. Returns integer argument containing either KDTEXT or KDGRAPHICS as defined in the KDSETMODE ioctl description. KDENABIO Enable in's and out's to video adaptor ports. No argu- ment. KDDISABIO Disable in's and out's to video adaptor ports. No argument. KDGKBTYPE Always returns 0. KIOCINFO Always returns 0x6B64. VTSETMODE Sets the virtual terminal mode. The argument is a pointer to a vtmode structure, as defined below. VTGETMODE Determines what mode the active virtual terminal is currently in, either VTAUTO or VTPROCESS. The argu- ment to the ioctl is the address of the following 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 */ The vtmode structure will be filled in with the current value for each field. VTRELDISP Tells the virtual terminal manager whether the display has been released by the process. 0 release refused 1 release acknowledged 2 acquire acknowledged VTACTIVATE Makes the multiscreen number specified in the argument the active multiscreen. The video driver will cause a switch to occur in the same manner as if a hotkey sequence had been typed at the keyboard. If the speci- fied multiscreen is not open or does not exist, the call will fail and errno will be set to EINVAL. Graphics adapter port I/O You can use ioctl(S) to read or write a byte from or to the graphics adapter port. The arg parameter of the ioctl call uses the portioarg data structure: struct port_io_arg { struct port_io_struct args[4]; }; As shown above, the portioarg structure points to an array of four portiostruct data structures. The portiostruct structure has the fol- lowing format: struct port_io_struct { char dir; /* direction flag (in vs. out) */ unsigned short port; /* port address */ char data; /* byte of data */ }; You may specify one, two, three, or four of the portiostruct structures in the array for one ioctl call. The value of dir can be either INONPORT to specify a byte being input to the graphics adapter port or OUTONPORT to specify a byte being output to the graphics adapter port. port is an integer specifying the port address of the desired graphics adapter port. data is the byte of data being input or output as speci- fied by the call. If you are not using any of the portiostruct structures, load the port with 0, and leave the unused structures at the end of the array. Refer to hardware manuals for port addresses and functions for the various adapters. You can use the following ioctl(S) commands to input or output a 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 array adapter port as specified. (VGA only) To input a byte on any of the graphics adapter ports, load dir with INONPORT and load port with the port address of the graphics adapter. The byte input from the graphics adapter port will be returned in data. To output a byte, load dir with OUTONPORT, load port with the port address of the graphics adapter, and load data with the byte you want output to the graphics adapter port. Function keys ioctl(S) can be used to define or obtain the current definition of a function key. The arg parameter of the ioctl call uses the fkeyarg data structure: struct fkeyarg { unsigned short keynum; char keydef [MAXFK]; char flen; } You can use the following ioctl(S) request to assign function key defini- tions: SETLOCKLOCK Toggles the Caps Lock and Num Lock keys to be either global to all the multiscreens, or local to each indi- vidual multiscreen. To make the Caps Lock global (its default), set the arg parameter to 1. To make the Caps Lock local to each screen, set the arg parameter to 0. ANSI screen attribute sequences The following character sequences are defined by ANSI X3.64-1979 and may be used to control and modify the screen display. Each n is replaced by the appropriate ASCII number (decimal) to produce the desired effect. The last column is for termcap(M) codes, where ``n/a'' means not applica- ble. The use of 7 or 8 bit characters in the escape sequence is a valid invo- cation for each action defined. For example the ANSI ED command can be invoked via the ``ESC[n J'' (0x1b-0x5b-n-0x4a, 7 bit chars) sequence or the ``CSInJ'' (0x9b-n-0x4n, 8 bit chars) sequence. _________________________________________________________________________ ISO Sequence Action Termcap Code _________________________________________________________________________ ED CSInJ Erases all or part of a cd (Erase in display. n=0: erases from Display) active position to end of display. n=1: erases from the beginning of display to active position. n=2: erases entire display. EL CSInK Erases all or part of a line. ce (Erase in n=0: erases from active posi- Line) tion to end of line. n=1: erases from beginning of line to active position. n=2: erases entire line. ECH CSInX Erases n characters. n/a (Erase Character) CBT CSInZ Moves active position back n bt (Cursor tab stops. Backward Tabulation) SU CSInS Scrolls screen up n lines, sf (Scroll introducing new blank lines Up) at bottom. SD CSInT Scrolls screen down n lines, sr (Scroll introducing new blank lines Down) at top. CUP CSIm;nH Moves active position to cm (Cursor location m (vertical) and n Position) (horizontal). HVP CSIm;nf Moves active position to n/a (Horizontal location m (vertical) and n & Vertical (horizontal). Position) CUU CSInA Moves active position up n up (ku) (Cursor Up) number of lines. CUD CSInB Moves active position down n do (kd) (Cursor number of lines. Down) CUF CSInC Moves active position n nd (kr) (Cursor spaces to the right. Forward) CUB CSInD Moves active position n bs (kl) (Cursor spaces backward. Backward) HPA CSIn Moves active position to n/a (Horizontal column given by n. Position Absolute) HPR CSIna Moves active position n char- n/a (Horizontal acters to the right. Position Relative) VPA CSInd Moves active position to line n/a (Vertical given by n. Position Absolute) VPR CSIne Moves active position down n n/a (Vertical number of lines. Position Relative) IL CSInL Inserts n new, blank lines. al (Insert Line) ICH CSIn@ Inserts n blank places for n ic (Insert characters. Character) DL CSInM Deletes n lines. dl (Delete Line) DCH CSInP Deletes n number of charac- dc (Delete ters. Character) CPL CSInF Moves active position to n/a (Cursor to beginning of line, n lines Previous up. Line) CNL CSInE Moves active position to n/a (Cursor beginning of line, n lines Next down. Line) SGR CSInm Character attributes, as sum- n/a (Select marized in the chart below. Graphic Up to three attributes can be Rendition) specified in the form: CSI n1; n2; n3 m (See list of parameters below.) SM CSI2h Locks keyboard. Ignores key- n/a (Set Mode) board input until unlocked. Characters are not saved. MC CSI2i Sends screen to host. n/a (Media Current screen contents are Copy) sent to the application. RM CSI2l Unlocks keyboard. Re-enables n/a (Reset keyboard input. Mode) Select Graphic Rendition (SGR) Chart _________________________________________________________________________ n Meaning _________________________________________________________________________ 0 all attributes off (normal display) 1 bold intensity (or light color) 4 underscore on (if hardware supports it) 5 blink on (if hardware supports it) 7 reverse video 8 sets blank (non-display) 10 selects the primary font 11 selects the first alternate font; lets ASCII characters less than 32 be displayed as ROM characters 12 selects a second alternate font; toggles high bit of extended ASCII code before displaying as ROM characters 30 black foreground 31 red foreground 32 green foreground 33 brown foreground 34 blue foreground 35 magenta foreground 36 cyan foreground 37 white foreground 38 enables underline option; white foreground with white underscore 39 disables underline option 40 black background 41 red background 42 green background 43 brown background 44 blue background 45 magenta background 46 cyan background 47 white background Additional screen attribute sequences _________________________________________________________________________ Termcap Name Sequence Action Code _________________________________________________________________________ n/a CSI=p;dB Sets the bell parameter to n/a the decimal values of p and d. p is the period of the bell tone in units of 840.3 nanoseconds, and d is the duration of the tone in units of 100 milliseconds. n/a CSI=s;eC Sets the cursor to start on n/a scanline s and end on scan- line e. n/a CSI=xD Turns on or off (x=1 or 0) n/a the intensity of the back- ground color. n/a CSI=xE Sets or clears (x=1 or 0) the n/a Blink vs. Bold background bit in the 6845 CRT controller. n/a CSI=cA Sets overscan color to color n/a c. c is a decimal value taken from Color Table above. (This sequence may not be supported on all hardware.) n/a CSI=cF Sets normal foreground color n/a to c. (c is a decimal param- eter taken from Color Table.) n/a CSI=cG Sets normal background. n/a (See Color Table.) n/a CSI=cH Sets reverse foreground. n/a (See Color Table.) n/a CSI=cI Sets reverse background. n/a (See Color Table.) n/a CSI=cJ Sets graphic foreground. n/a (See Color Table.) n/a CSI=cK Sets graphic background. n/a (See Color Table.) n/a CSIng Accesses alternate graphics n/a set. Not the same as ``graphics mode''. Refer to your hardware manual for decimal/character codes (Pn) and possible output charac- ters. n/a CSInL Fills new regions with n/a current (n=0) or normal (n=1) attributes. Default is 0. n/a CSInM Returns current foreground n/a color attributes, with n=0 for normal, 1 for reverse, and 2 for graphic. The colors are sent back in the keyboard data input stream as text decimal values separated by a space and terminated with a newline. For example, if the current foreground color is lt_red on black, ``12 0\n'' is returned. n/a CSIs Saves current cursor posi- n/a tion. n/a CSIu Restores saved cursor posi- n/a tion. n/a ESC7 Saves current cursor posi- n/a tion. n/a ESC8 Restores saved cursor posi- n/a tion. n/a ESCQ Fn 'string' Defines function key Fn with n/a string. String delimiters ' and ' may be any character not in string. Fn is defined as the key number starting at zero plus the ASCII value of zero. For example, F1 = 0... F16 = `` ? '', and so on. In this escape sequence, the `` ^ '' character will cause the next character to have 32 subtracted from its ASCII value. Thus `` ^! '' results in a SOH (^A) character. n/a CSInz Switches to screen n. If the n/a screen does not exist, no action will take place. Color Table _________________________________________________________________________ Cn Color Cn Color _________________________________|_______________________________________ 0 Black | 8 Grey 1 Blue | 9 Lt. Blue 2 Green | 10 Lt. Green 3 Cyan | 11 Lt. Cyan 4 Red | 12 Lt. Red 5 Magenta | 13 Lt. Magenta 6 Brown | 14 Yellow 7 White | 15 Lt. White Examples The following module includes useful examples of such operations as get- ting the display mode, screen switching, I/O privilege, and memory map- ping. Sample code (part 1 of 4) #include <stdio.h> #include <sys/types.h> #include <sys/signal.h> #include <sys/vtkd.h> #define SIG_REL SIGUSR1 #define SIG_ACQ SIGUSR2 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. */ void rel_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. */ void acq_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); } void grafquit() { grafend(); exit(0); } Sample code (3 of 4) /* * restore text mode. */ void grafend() { 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\n"); 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; else privlcmd = 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); } Files /dev/console /dev/tty[02-n] /dev/color /dev/monochrome /dev/ega /dev/vga Include files: /usr/include/sys/vtkd.h /usr/include/sys/comcrt.h /usr/include/sys/console.h /usr/include/sys/kb.h See also console(M), ioctl(S), keyboard(HW), keymap(M), mapkey(M), mapchan(M), multiscreen(M), scancode(HW), setcolor(C), stty(C), systty(M), vidi(C), termcap(M), tty(M)