分享
 
 
 

C语言库函数 (D类字母)

王朝c/c++·作者佚名  2008-06-01
窄屏简体版  字體: |||超大  

[ 发表日期:2002-1-4 9:28:46

]

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 <dos.h>

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 <conio.h>

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 <graphics.h>

#include <stdlib.h>

#include <stdio.h>

#include <conio.h>

/* 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 Hercules monochrome",

"an AT&T 6300 PC",

"a VGA",

"an IBM 3270 PC"

};

int main(void)

{

/* returns detected hardware

info. */

int gdriver, gmode, errorcode;

/* detect graphics hardware

available */

detectgraph(&gdriver,

&gmode);

/* read result of detectgraph

call */

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 */

}

/* display the information

detected */

clrscr();

printf("You have %s

video display \

card.\n", dname[gdriver]);

printf("Press any key

to halt:");

getch();

return 0;

}

函数名: difftime

功 能: 计算两个时刻之间的时间差

用 法: double difftime(time_t

time2, time_t time1);

程序例:

#include <time.h>

#include <stdio.h>

#include <dos.h>

#include <conio.h>

int main(void)

{

time_t first, second;

clrscr();

first = time(NULL); /* Gets

system

time */

delay(2000); /* Waits 2

secs */

second = time(NULL); /*

Gets system time

again */

printf("The difference

is: %f \

seconds\n",difftime(second,first));

getch();

return 0;

}

函数名: disable

功 能: 屏蔽中断

用 法: void disable(void);

程序例:

/***NOTE: This is an interrupt

service

routine. You cannot compile

this program

with Test Stack Overflow

turned on and

get an executable file that

operates

correctly. */

#include <stdio.h>

#include <dos.h>

#include <conio.h>

#define INTR 0X1C /* The

clock tick

interrupt */

void interrupt ( *oldhandler)(void);

int count=0;

void interrupt handler(void)

{

/* disable interrupts during

the handling of

the interrupt */

disable();

/* increase the global counter

*/

count++;

/* reenable interrupts at

the end of the

handler */

enable();

/* call the old routine

*/

oldhandler();

}

int main(void)

{

/* save the old interrupt

vector */

oldhandler = getvect(INTR);

/* install the new interrupt

handler */

setvect(INTR, handler);

/* loop until the counter

exceeds 20 */

while (count < 20)

printf("count is %d\n",count);

/* reset the old interrupt

handler */

setvect(INTR, oldhandler);

return 0;

}

函数名: div

功 能: 将两个整数相除, 返回商和余数

用 法: div_t (int number,

int denom);

程序例:

#include <stdlib.h>

#include <stdio.h>

div_t x;

int main(void)

{

x = div(10,3);

printf("10 div 3 =

%d remainder %d\n",

x.quot, x.rem);

return 0;

}

函数名: dosexterr

功 能: 获取扩展DOS错误信息

用 法: int dosexterr(strUCt

DOSERR *dblkp);

程序例:

#include <stdio.h>

#include <dos.h>

int main(void)

{

FILE *fp;

struct DOSERROR info;

fp = fopen("perror.dat","r");

if (!fp) perror("Unable

to open file for

reading");

dosexterr(&info);

printf("Extended DOS

error \

information:\n");

printf(" Extended error:

\

%d\n",info.exterror);

printf(" Class: \

%x\n",info.class);

printf(" Action: \

%x\n",info.action);

printf(" Error Locus:

\

%x\n",info.locus);

return 0;

}

函数名: dostounix

功 能: 转换日期和时间为UNIX时间格式

用 法: long dostounix(struct

date *dateptr, struct time

*timeptr);

程序例:

#include <time.h>

#include <stddef.h>

#include <dos.h>

#include <stdio.h>

int main(void)

{

time_t t;

struct time d_time;

struct date d_date;

struct tm *local;

getdate(&d_date);

gettime(&d_time);

t = dostounix(&d_date,

&d_time);

local = localtime(&t);

printf("Time and Date:

%s\n", \

asctime(local));

return 0;

}

函数名: drawpoly

功 能: 画多边形

用 法: void far drawpoly(int

numpoints, int far *polypoints);

程序例:

#include <graphics.h>

#include <stdlib.h>

#include <stdio.h>

#include <conio.h>

int main(void)

{

/* request auto detection

*/

int gdriver = DETECT, gmode,

errorcode;

int maxx, maxy;

/* our polygon array */

int poly[10];

/* 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();

/* terminate with an error

code */

exit(1);

}

maxx = getmaxx();

maxy = getmaxy();

poly[0] = 20; /* 1st vertext

*/

poly[1] = maxy / 2;

poly[2] = maxx - 20; /*

2nd */

poly[3] = 20;

poly[4] = maxx - 50; /*

3rd */

poly[5] = maxy - 20;

poly[6] = maxx / 2; /*

4th */

poly[7] = maxy / 2;

/*

drawpoly doesn't automatically

close

the polygon, so we close

it.

*/

poly[8] = poly[0];

poly[9] = poly[1];

/* draw the polygon */

drawpoly(5, poly);

/* clean up */

getch();

closegraph();

return 0;

}

函数名: dup

功 能: 复制一个文件句柄

用 法: int dup(int handle);

程序例:

#include <string.h>

#include <stdio.h>

#include <conio.h>

#include <io.h>

void flush(FILE *stream);

int main(void)

{

FILE *fp;

char msg[] = "This

is a test";

/* create a file */

fp = fopen("DUMMY.FIL",

"w");

/* write some data to the

file */

fwrite(msg, strlen(msg),

1, fp);

clrscr();

printf("Press any key

to flush \

DUMMY.FIL:");

getch();

/* flush the data to DUMMY.FIL

without

closing it */

flush(fp);

printf("\nFile was

flushed, Press any \

key to quit:");

getch();

return 0;

}

void flush(FILE *stream)

{

int duphandle;

/* flush TC's internal

buffer */

fflush(stream);

/* make a duplicate file

handle */

duphandle = dup(fileno(stream));

/* close the duplicate

handle to flush the

DOS buffer */

close(duphandle);

}

函数名: dup2

功 能: 复制文件句柄

用 法: int dup2(int oldhandle,

int newhandle);

程序例:

#include <sys\stat.h>

#include <string.h>

#include <fcntl.h>

#include <io.h>

int main(void)

{

#define STDOUT 1

int nul, oldstdout;

char msg[] = "This

is a test";

/* create a file */

nul = open("DUMMY.FIL",

O_CREAT O_RDWR,

S_IREAD S_IWRITE);

/* create a duplicate handle

for standard

output */

oldstdout = dup(STDOUT);

/*

redirect standard output

to DUMMY.FIL

by duplicating the file

handle onto the

file handle for standard

output.

*/

dup2(nul, STDOUT);

/* close the handle for

DUMMY.FIL */

close(nul);

/* will be redirected into

DUMMY.FIL */

write(STDOUT, msg, strlen(msg));

/* restore original standard

output

handle */

dup2(oldstdout, STDOUT);

/* close duplicate handle

for STDOUT */

close(oldstdout);

return 0;

}

 
 
 
免责声明:本文为网络用户发布,其观点仅代表作者个人观点,与本站无关,本站仅提供信息存储服务。文中陈述内容未经本站证实,其真实性、完整性、及时性本站不作任何保证或承诺,请读者仅作参考,并请自行核实相关内容。
2023年上半年GDP全球前十五强
 百态   2023-10-24
美众议院议长启动对拜登的弹劾调查
 百态   2023-09-13
上海、济南、武汉等多地出现不明坠落物
 探索   2023-09-06
印度或要将国名改为“巴拉特”
 百态   2023-09-06
男子为女友送行,买票不登机被捕
 百态   2023-08-20
手机地震预警功能怎么开?
 干货   2023-08-06
女子4年卖2套房花700多万做美容:不但没变美脸,面部还出现变形
 百态   2023-08-04
住户一楼被水淹 还冲来8头猪
 百态   2023-07-31
女子体内爬出大量瓜子状活虫
 百态   2023-07-25
地球连续35年收到神秘规律性信号,网友:不要回答!
 探索   2023-07-21
全球镓价格本周大涨27%
 探索   2023-07-09
钱都流向了那些不缺钱的人,苦都留给了能吃苦的人
 探索   2023-07-02
倩女手游刀客魅者强控制(强混乱强眩晕强睡眠)和对应控制抗性的关系
 百态   2020-08-20
美国5月9日最新疫情:美国确诊人数突破131万
 百态   2020-05-09
荷兰政府宣布将集体辞职
 干货   2020-04-30
倩女幽魂手游师徒任务情义春秋猜成语答案逍遥观:鹏程万里
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案神机营:射石饮羽
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案昆仑山:拔刀相助
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案天工阁:鬼斧神工
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案丝路古道:单枪匹马
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:与虎谋皮
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:李代桃僵
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:指鹿为马
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案金陵:小鸟依人
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案金陵:千金买邻
 干货   2019-11-12
 
推荐阅读
 
 
 
>>返回首頁<<
 
靜靜地坐在廢墟上,四周的荒凉一望無際,忽然覺得,淒涼也很美
© 2005- 王朝網路 版權所有