博文
函数大全(a开头)(2006-06-16 10:15:00)
摘要：
函数名: abort 功 能: 异常终止一个进程 用 法: void abort(void); 程序例: #include #include
int main(void) { printf("Calling abort()\n"); abort(); return 0; /* This is never reached */ }
函数名: abs 功 能: 求整数的绝对值 用 法: int abs(int i); 程序例: #include #include
int main(void) { int number = -1234;
printf("number: %d absolute value: %d\n", number, abs(number)); return 0; }
函数名: absread, abswirte 功 能: 绝对磁盘扇区读、写数据 用 法: int absread(int drive, int nsects, int sectno, void *buffer); int abswrite(int drive, int nsects, in tsectno, void *buffer); 程序例: /* absread example */
#include #include #include #include
int main(void) { int i, strt, ch_out, sector; char buf[512];
printf("Insert a diskette into drive A and press any key\n"); getch(); sector = 0; if (absread(0, 1, sector, &buf) != 0) { perror("Disk problem"); exit(1); } printf("Read OK\n"); strt = 3; for (i=0; i<80; i++) { ch_out = buf[strt+i]; putchar(ch_out); } printf("\n"); return(0); }
函数名: access 功 能: 确定文件的访问权限 用 法: int access(const char ......
函数大全(b开头)(2006-06-16 10:14:00)
摘要：函数名: bar 功 能: 画一个二维条形图 用 法: void far bar(int left, int top, int right, int bottom); 程序例:
#include #include #include #include
int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy, i;
/* 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 */ }
midx = getmaxx() / 2; midy = getmaxy() / 2;
/* loop through the fill patterns */ for (i=SOLID_FILL; i......
函数大全(c开头)(2006-06-16 10:10:00)
摘要：函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 程序例:
#include #include
int main(void) { struct complex z; double val;
z.x = 2.0; z.y = 1.0; val = cabs(z);
printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; }
函数名: calloc 功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); 程序例:
#include #include
int main(void) { char *str = NULL;
/* allocate memory for string */ str = calloc(10, sizeof(char));
/* copy "Hello" into string */ strcpy(str, "Hello");
/* display string */ printf("String is %s\n", str);
/* free memory */ free(str);
return 0; }
函数名: ceil 功 能: 向上舍入 用 法: double ceil(double x); 程序例:
#include #include
int main(void) { double number = 123.54; double down, up;
down = floor(number); up = ceil(number);
printf("original number %5.2lf\n", number); printf("number rounded down %5.2lf\n", down); printf("number rounded up %5.2lf\n", up);
return 0; }
函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); 程序例......
函数大全(d开头)(2006-06-16 10:09:00)
摘要：函数名: delay 功 能: 将程序的执行暂停一段时间(毫秒) 用 法: void delay(unsigned milliseconds); 程序例: /* Emits a 440-Hz tone for 500 milliseconds */ #include
int main(void) { sound(440); delay(500); nosound();
return 0; }
函数名: delline 功 能: 在文本窗口中删去一行 用 法: void delline(void); 程序例:
#include
int main(void) { clrscr(); cprintf("The function DELLINE deletes \ the line containing the\r\n"); cprintf("cursor and moves all lines \ below it one line up.\r\n"); cprintf("DELLINE operates within the \ currently active text\r\n"); cprintf("window. Press any key to \ continue . . ."); gotoxy(1,2); /* Move the cursor to the second line and first column */ getch();
delline(); getch();
return 0; }
函数名: detectgraph 功 能: 通过检测硬件确定图形驱动程序和模式 用 法: void far detectgraph(int far *graphdriver, int far *graphmode); 程序例:
#include #include #include #include
/* names of the various cards supported */ char *dname[] = { "requests detection", "a CGA", "an MCGA", "an EGA", "a 64K EGA", "a monochrome EGA", "an IBM 8514", "a H......
函数大全(e开头)(2006-06-16 10:07:00)
摘要：函数名: ecvt 功 能: 把一个浮点数转换为字符串 用 法: char ecvt(double value, int ndigit, int *decpt, int *sign); 程序例:
#include #include #include
int main(void) { char *string; double value; int dec, sign; int ndig = 10;
clrscr(); value = 9.876; string = ecvt(value, ndig, &dec, &sign); printf("string = %s dec = %d \ sign = %d\n", string, dec, sign);
value = -123.45; ndig= 15; string = ecvt(value,ndig,&dec,&sign); printf("string = %s dec = %d sign = %d\n", string, dec, sign);
value = 0.6789e5; /* scientific notation */ ndig = 5; string = ecvt(value,ndig,&dec,&sign); printf("string = %s dec = %d\ sign = %d\n", string, dec, sign);
return 0; }
函数名: ellipse 功 能: 画一椭圆 用 法: void far ellipse(int x, int y, int stangle, int endangle, int xradius, int yradius); 程序例:
#include #include #include #include
int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy; int stangle = 0, endangle = 360; int xradius = 100, yradius = 50;
/* init......
函数大全(f开头)(2006-06-16 10:06:00)
摘要：double fabs(double x);
返回双精度x的绝对值。
void far *farcalloc(unsigned long nunits,unsigned long unitsz);
堆中给含有nu从远nits个元素的，每个元素占用unitsz个字节长的数组分配存贮区。成功是返回指向新分配的内存块的指针；若存贮空间不够，返回NULL。
unsigned long farcoreleft(void);
返回远堆中未用存贮区的大小。
void farfree(void far *block);
释放远堆中以前所分配内存块。
void far *farmalloc(unsigned long nbytes);
从远堆分配长nbytes字节的内存块，返回新地址。
void far *farrealloc(void far *oldblock,unsigned long nbytes);
调整已分配的内存块的大小为nbytes。需要的话，可把块中的内容复制到新位置。要注意：所有的可用的RAM可被分配，大于64K的块可被分配。远指针用于存取被分配的块。返回重新分配的内存块的地址。若存贮块重新分配失败，返回NULL。
struct fcb {
char fcb_drive; /* 0 = default, 1 = A, 2 = B */
char fcb_name[8]; /* File name */
char fcb_ext[3]; /* File extension */
short fcb_curblk; /* Current block number */
short fcb_recsize; /* Logical record size in bytes */
long fcb_filsize; /* File size in bytes */
short fcb_date; /* Date file was last written */
char fcb_resv[10]; /* Reserved for DOS */
char fcb_currec; /* Current record in block */
long fcb_random; /* Random recor......
函数大全(g开头)(2006-06-16 10:05:00)
摘要：
函数名: gcvt 功 能: 把浮点数转换成字符串 用 法: char *gcvt(double value, int ndigit, char *buf); 程序例:
#include #include
int main(void) { char str[25]; double num; int sig = 5; /* significant digits */
/* a regular number */ num = 9.876; gcvt(num, sig, str); printf("string = %s\n", str);
/* a negative number */ num = -123.4567; gcvt(num, sig, str); printf("string = %s\n", str);
/* scientific notation */ num = 0.678e5; gcvt(num, sig, str); printf("string = %s\n", str);
return(0); }
函数名: geninterrupt 功 能: 产生一个软中断 用 法: void geninterrupt(int intr_num); 程序例:
#include #include
/* function prototype */ void writechar(char ch);
int main(void) { clrscr(); gotoxy(80,25); writechar('*'); getch(); return 0; }
/* outputs a character at the current cursor position using the video BIOS to avoid the scrolling of the screen when writing to location (80,25). */
void writechar(char ch) { struct text_info ti; /* grab current text settings */ gettextinfo(&ti); /* interrupt 0x10 sub-function 9 *......
函数大全(h开头)(2006-06-16 10:03:00)
摘要：函数名: harderr 功 能: 建立一个硬件错误处理程序 用 法: void harderr(int (*fptr)()); 程序例: /*This program will trap disk errors and prompt the user for action. Try running it with no disk in drive A: to invoke its functions.*/
#include #include #include #define IGNORE 0 #define RETRY 1 #define ABORT 2 int buf[500]; /*define the error messages for trapping disk problems*/ static char *err_msg[] = { "write protect", "unknown unit", "drive not ready", "unknown command", "data error (CRC)", "bad request", "seek error", "unknown media type", "sector not found", "printer out of paper", "write fault", "read fault", "general failure", "reserved", "reserved", "invalid disk change" };
error_win(char *msg) { int retval;
cputs(msg);
/*prompt for user to press a key to abort, retry, ignore*/ while(1) { retval= getch(); if (retval == 'a' || retval == 'A') { retval = ABORT; break; } if (retval == 'r' || retval == 'R') { retval = RETRY; break; } if (retval == 'i' || retval == 'I') { retval = IGNORE; break; } }
r......
函数大全(i开头)(2006-06-16 10:02:00)
摘要：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-A......
函数大全(k开头)(2006-06-16 10:00:00)
摘要：函数名: kbhit 功 能: 检查当前按下的键 用 法: int kbhit(void); 程序例:
#include
int main(void) { cprintf("Press any key to continue:"); while (!kbhit()) /* do nothing */ ; cprintf("\r\nA key was pressed...\r\n"); return 0; }
函数名: keep 功 能: 退出并继续驻留 用 法: void keep(int status, int size); 程序例:
/***NOTE: This is an interrupt service routine. You can NOT compile this program with Test Stack Overflow turned on and get an executable file which will operate correctly. Due to the nature of this function the formula used to compute the number of paragraphs may not necessarily work in all cases. Use with care! Terminate Stay Resident (TSR) programs are complex and no other support for them is provided. Refer to the MS-DOS technical documentation for more information. */ #include /* The clock tick interrupt */ #define INTR 0x1C /* Screen attribute (blue on grey) */ #define ATTR 0x7900
/* reduce heaplength and stacklength to make a smaller program in memory */ extern unsigned _heaplen = 1024; extern unsigned......