函数名: imagesize
功 能: 返回保存位图像所需的字节数
用 法: unsigned far imagesize(int left, int top, int right, int bottom);
程序例:
#include#include #include #include #define ARROW_SIZE 10 void draw_arrow(int x, int y); int main(void) { /* request autodetection */ int gdriver = DETECT, gmode, errorcode; void *arrow; int x, y, maxx; unsigned int size; /* initialize graphics and local variables */ initgraph(&gdriver, &gmode, ""); /* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ } maxx = getmaxx(); x = 0; y = getmaxy() / 2; /* draw the image to be grabbed */ draw_arrow(x, y); /* calculate the size of the image */ size = imagesize(x, y-ARROW_SIZE, x+(4*ARROW_SIZE), y+ARROW_SIZE); /* allocate memory to hold the image */ arrow = malloc(size); /* grab the image */ getimage(x, y-ARROW_SIZE, x+(4*ARROW_SIZE), y+ARROW_SIZE, arrow); /* repeat until a key is pressed */ while (!kbhit()) { /* erase old image */ putimage(x, y-ARROW_SIZE, arrow, XOR_PUT); x += ARROW_SIZE; if (x >= maxx) x = 0; /* plot new image */ putimage(x, y-ARROW_SIZE, arrow, XOR_PUT); } /* clean up */ free(arrow); closegraph(); return 0; } void draw_arrow(int x, int y) { /* draw an arrow on the screen */ moveto(x, y); linerel(4*ARROW_SIZE, 0); linerel(-2*ARROW_SIZE, -1*ARROW_SIZE); linerel(0, 2*ARROW_SIZE); linerel(2*ARROW_SIZE, -1*ARROW_SIZE); }
函数名: initgraph
功 能: 初始化图形系统
用 法: void far initgraph(int far *graphdriver, int far *graphmode,
char far *pathtodriver);
程序例:
#include#include #include #include int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; /* initialize graphics mode */ initgraph(&gdriver, &gmode, ""); /* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* return with error code */ } /* draw a line */ line(0, 0, getmaxx(), getmaxy()); /* clean up */ getch(); closegraph(); return 0; }
函数名: inport
功 能: 从硬件port中输入
用 法: int inp(int protid);
程序例:
#include#include int main(void) { int result; int port = 0; /* serial port 0 */ result = inport(port); printf("Word read from port %d = 0x%X\n", port, result); return 0; }
函数名: insline
功 能: 在文本窗体中插入一个空行
用 法: void insline(void);
程序例:
#includeint main(void) { clrscr(); cprintf("INSLINE inserts an empty line in the text window\r\n"); cprintf("at the cursor position using the current text\r\n"); cprintf("background color. All lines below the empty one\r\n"); cprintf("move down one line and the bottom line scrolls\r\n"); cprintf("off the bottom of the window.\r\n"); cprintf("\r\nPress any key to continue:"); gotoxy(1, 3); getch(); insline(); getch(); return 0; }
函数名: installuserdriver
功 能: 安装设备驱动程序到BGI设备驱动程序表中
用 法: int far installuserdriver(char far *name, int (*detect)(void));
程序例:
#include#include #include #include /* function prototypes */ int huge detectEGA(void); void checkerrors(void); int main(void) { int gdriver, gmode; /* install a user written device driver */ gdriver = installuserdriver("EGA", detectEGA); /* must force use of detection routine */ gdriver = DETECT; /* check for any installation errors */ checkerrors(); /* initialize graphics and local variables */ initgraph(&gdriver, &gmode, ""); /* check for any initialization errors */ checkerrors(); /* draw a line */ line(0, 0, getmaxx(), getmaxy()); /* clean up */ getch(); closegraph(); return 0; } /* detects EGA or VGA cards */ int huge detectEGA(void) { int driver, mode, sugmode = 0; detectgraph(&driver, &mode); if ((driver == EGA) || (driver == VGA)) /* return suggested video mode number */ return sugmode; else /* return an error code */ return grError; } /* check for and report any graphics errors */ void checkerrors(void) { int errorcode; /* read result of last graphics operation */ errorcode = graphresult(); if (errorcode != grOk) { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); } }
函数名: installuserfont
功 能: 安装未嵌入BGI系统的字体文件(CHR)
用 法: int far installuserfont(char far *name);
程序例:
#include#include #include #include /* function prototype */ void checkerrors(void); int main(void) { /* request auto detection */ int gdriver = DETECT, gmode; int userfont; int midx, midy; /* initialize graphics and local variables */ initgraph(&gdriver, &gmode, ""); midx = getmaxx() / 2; midy = getmaxy() / 2; /* check for any initialization errors */ checkerrors(); /* install a user defined font file */ userfont = installuserfont("USER.CHR"); /* check for any installation errors */ checkerrors(); /* select the user font */ settextstyle(userfont, HORIZ_DIR, 4); /* output some text */ outtextxy(midx, midy, "Testing!"); /* clean up */ getch(); closegraph(); return 0; } /* check for and report any graphics errors */ void checkerrors(void) { int errorcode; /* read result of last graphics operation */ errorcode = graphresult(); if (errorcode != grOk) { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); } }
函数名: int86
功 能: 通用8086软中断接口
用 法: int int86(int intr_num, union REGS *inregs, union REGS *outregs);
程序例:
#include#include #include #define VIDEO 0x10 void movetoxy(int x, int y) { union REGS regs; regs.h.ah = 2; /* set cursor postion */ regs.h.dh = y; regs.h.dl = x; regs.h.bh = 0; /* video page 0 */ int86(VIDEO, ®s, ®s); } int main(void) { clrscr(); movetoxy(35, 10); printf("Hello\n"); return 0; }
函数名: int86x
功 能: 通用8086软中断接口
用 法: int int86x(int intr_num, union REGS *insegs, union REGS *outregs,
struct SREGS *segregs);
程序例:
#include#include #include int main(void) { char filename[80]; union REGS inregs, outregs; struct SREGS segregs; printf("Enter filename: "); gets(filename); inregs.h.ah = 0x43; inregs.h.al = 0x21; inregs.x.dx = FP_OFF(filename); segregs.ds = FP_SEG(filename); int86x(0x21, &inregs, &outregs, &segregs); printf("File attribute: %X\n", outregs.x.cx); return 0; }
函数名: intdos
功 能: 通用DOS接口
用 法: int intdos(union REGS *inregs, union REGS *outregs);
程序例:
#include#include /* deletes file name; returns 0 on success, nonzero on failure */ int delete_file(char near *filename) { union REGS regs; int ret; regs.h.ah = 0x41; /* delete file */ regs.x.dx = (unsigned) filename; ret = intdos(®s, ®s); /* if carry flag is set, there was an error */ return(regs.x.cflag ? ret : 0); } int main(void) { int err; err = delete_file("NOTEXIST.$$$"); if (!err) printf("Able to delete NOTEXIST.$$$\n"); else printf("Not Able to delete NOTEXIST.$$$\n"); return 0; }
函数名: intdosx
功 能: 通用DOS中断接口
用 法: int intdosx(union REGS *inregs, union REGS *outregs,
struct SREGS *segregs);
程序例:
#include#include /* deletes file name; returns 0 on success, nonzero on failure */ int delete_file(char far *filename) { union REGS regs; struct SREGS sregs; int ret; regs.h.ah = 0x41; /* delete file */ regs.x.dx = FP_OFF(filename); sregs.ds = FP_SEG(filename); ret = intdosx(®s, ®s, &sregs); /* if carry flag is set, there was an error */ return(regs.x.cflag ? ret : 0); } int main(void) { int err; err = delete_file("NOTEXIST.$$$"); if (!err) printf("Able to delete NOTEXIST.$$$\n"); else printf("Not Able to delete NOTEXIST.$$$\n"); return 0; }
函数名: intr
功 能: 改变软中断接口
用 法: void intr(int intr_num, struct REGPACK *preg);
程序例:
#include#include #include #include #define CF 1 /* Carry flag */ int main(void) { char directory[80]; struct REGPACK reg; printf("Enter directory to change to: "); gets(directory); reg.r_ax = 0x3B << 8; /* shift 3Bh into AH */ reg.r_dx = FP_OFF(directory); reg.r_ds = FP_SEG(directory); intr(0x21, ®); if (reg.r_flags & CF) printf("Directory change failed\n"); getcwd(directory, 80); printf("The current directory is: %s\n", directory); return 0; }
函数名: ioctl
功 能: 控制I/O设备
用 法: int ioctl(int handle, int cmd[,int *argdx, int argcx]);
程序例:
#include#include #include int main(void) { int stat; /* use func 8 to determine if the default drive is removable */ stat = ioctl(0, 8, 0, 0); if (!stat) printf("Drive %c is removable.\n", getdisk() + 'A'); else printf("Drive %c is not removable.\n", getdisk() + 'A'); return 0; }
函数名: isatty
功 能: 检查设备类型
用 法: int isatty(int handle);
程序例:
#include#include int main(void) { int handle; handle = fileno(stdprn); if (isatty(handle)) printf("Handle %d is a device type\n", handle); else printf("Handle %d isn't a device type\n", handle); return 0; }
函数名: itoa
功 能: 把一整数转换为字符串
用 法: char *itoa(int value, char *string, int radix);
程序例:
#include#include int main(void) { int number = 12345; char string[25]; itoa(number, string, 10); printf("integer = %d string = %s\n", number, string); return 0; }