L.xml

标签：style   http   color   io   os   ar   使用   for   sp   

函数名:?labs?

功??能:?取长整型绝对值?

用??法:?long?labs(long?n);?

程序例:?

#include?<stdio.h>?
#include?<math.h>?
int?main(void)?
{?
???long?result;?
???long?x?=?-12345678L;?
???result=?labs(x);?
???printf("number:?%ld?abs?value:?%ld\n",?
??????x,?result);?
???return?0;?
}?
??
??
??

函数名:?ldexp?

功??能:?计算value*2的幂?

用??法:?double?ldexp(double?value,?int?exp);?

程序例:?

#include?<stdio.h>?
#include?<math.h>?
int?main(void)?
{?
???double?value;?
???double?x?=?2;?
???/*?ldexp?raises?2?by?a?power?of?3?
??????then?multiplies?the?result?by?2???*/?
???value?=?ldexp(x,3);?
???printf("The?ldexp?value?is:?%lf\n",?
??????value);?
???return?0;?
}?
??
??

函数名:?ldiv?

功??能:?两个长整型数相除,?返回商和余数?

用??法:?ldiv_t?ldiv(long?lnumer,?long?ldenom);?

程序例:?

/*?ldiv?example?*/?
#include?<stdlib.h>?
#include?<stdio.h>?
int?main(void)?
{?
???ldiv_t?lx;?
???lx?=?ldiv(100000L,?30000L);?
???printf("100000?div?30000?=?%ld?remainder?%ld\n",?lx.quot,?lx.rem);?
???return?0;?
}?
??
??
??

函数名:?lfind?

功??能:?执行线性搜索?

用??法:?void?*lfind(void?*key,?void?*base,?int?*nelem,?int?width,?

??????int?(*fcmp)());?

程序例:?

#include?<stdio.h>?
#include?<stdlib.h>?
int?compare(int?*x,?int?*y)?
{?
???return(?*x?-?*y?);?
}?
int?main(void)?
{?
???int?array[5]?=?{35,?87,?46,?99,?12};?
???size_t?nelem?=?5;?
???int?key;?
???int?*result;?
???key?=?99;?
???result?=?lfind(&key,?array,?&nelem,?
????????sizeof(int),?(int(*)(const?void?*,const?void?*))compare);?
???if?(result)?
??????printf("Number?%d?found\n",key);?
???else?
??????printf("Number?%d?not?found\n",key);?
???return?0;?
}?
??
??

函数名:?line?

功??能:?在指定两点间画一直线?

用??法:?void?far?line(int?x0,?int?y0,?int?x1,?int?y1);?

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?xmax,?ymax;?
???/*?initialize?graphics?and?local?variables?*/?
???initgraph(&gdriver,?&gmode,?"");?
???/*?read?result?of?initialization?*/?
???errorcode?=?graphresult();?
???/*?an?error?occurred?*/?
???if?(errorcode?!=?grOk)?
???{?
??????printf("Graphics?error:?%s\n",?
?????????????grapherrormsg(errorcode));?
??????printf("Press?any?key?to?halt:");?
??????getch();?
??????exit(1);?
???}?
???setcolor(getmaxcolor());?
???xmax?=?getmaxx();?
???ymax?=?getmaxy();?
???/*?draw?a?diagonal?line?*/?
???line(0,?0,?xmax,?ymax);?
???/*?clean?up?*/?
???getch();?
???closegraph();?
???return?0;?
}?
??
??

函数名:?linerel?

功??能:?从当前位置点(CP)到与CP有一给定相对距离的点画一直线?

用??法:?void?far?linerel(int?dx,?int?dy);?

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;?
???char?msg[80];?
???/*?initialize?graphics?and?local?variables?*/?
???initgraph(&gdriver,?&gmode,?"");?
???/*?read?result?of?initialization?*/?
???errorcode?=?graphresult();?
???if?(errorcode?!=?grOk)?
???{?
??????printf("Graphics?error:?%s\n",?
??grapherrormsg(errorcode));?
??????printf("Press?any?key?to?halt:");?
??????getch();?
??????exit(1);?
???}?
???/*?move?the?C.P.?to?location?(20,?30)?*/?
???moveto(20,?30);?
???/*?create?and?output?a?
??????message?at?(20,?30)?*/?
???sprintf(msg,?"?(%d,?%d)",?getx(),?gety());?
???outtextxy(20,?30,?msg);?
???/*?draw?a?line?to?a?point?a?relative?
??????distance?away?from?the?current?
??????value?of?C.P.???*/?
???linerel(100,?100);?
???/*?create?and?output?a?message?at?C.P.?*/?
???sprintf(msg,?"?(%d,?%d)",?getx(),?gety());?
???outtext(msg);?
???/*?clean?up?*/?
???getch();?
???closegraph();?
???return?0;?
}?
??

函数名:?localtime?

功??能:?把日期和时间转变为结构?

用??法:?struct?tm?*localtime(long?*clock);?

程序例:?

#include?<time.h>?
#include?<stdio.h>?
#include?<dos.h>?
int?main(void)?
{?
???time_t?timer;?
???struct?tm?*tblock;?
???/*?gets?time?of?day?*/?
???timer?=?time(NULL);?
???/*?converts?date/time?to?a?structure?*/?
???tblock?=?localtime(&timer);?
???printf("Local?time?is:?%s",?asctime(tblock));?
???return?0;?
}?
??
??
??

函数名:?lock?

功??能:?设置文件共享锁?

用??法:?int?lock(int?handle,?long?offset,?long?length);?

程序例:?

#include?<io.h>?
#include?<fcntl.h>?
#include?<sys\stat.h>?
#include?<process.h>?
#include?<share.h>?
#include?<stdio.h>?
int?main(void)?
{?
???int?handle,?status;?
???long?length;?
???/*?Must?have?DOS?Share.exe?loaded?for?*/?
???/*?file?locking?to?function?properly?*/?
???handle?=?sopen("c:\\autoexec.bat",?
??????O_RDONLY,SH_DENYNO,S_IREAD);?
???if?(handle?<?0)?
???{?
??????printf("sopen?failed\n");?
??????exit(1);?
???}?
???length?=?filelength(handle);?
???status?=?lock(handle,0L,length/2);?
???if?(status?==?0)?
??????printf("lock?succeeded\n");?
???else?
??????printf("lock?failed\n");?
???status?=?unlock(handle,0L,length/2);?
???if?(status?==?0)?
??????printf("unlock?succeeded\n");?
???else?
??????printf("unlock?failed\n");?
???close(handle);?
???return?0;?
}?
??
??

函数名:?log?

功??能:?对数函数ln(x)?

用??法:?double?log(double?x);?

程序例:?

#include?<math.h>?
#include?<stdio.h>?
int?main(void)?
{?
???double?result;?
???double?x?=?8.6872;?
???result?=?log(x);?
???printf("The?natural?log?of?%lf?is?%lf\n",?x,?result);?
???return?0;?
}?
??
??

函数名:?log10?

功??能:?对数函数log?

用??法:?double?log10(double?x);?

程序例:?

#include?<math.h>?
#include?<stdio.h>?
int?main(void)?
{?
???double?result;?
???double?x?=?800.6872;?
???result?=?log10(x);?
???printf("The?common?log?of?%lf?is?%lf\n",?x,?result);?
???return?0;?
}?
??
??
??

函数名:?longjump?

功??能:?执行非局部转移?

用??法:?void?longjump(jmp_buf?env,?int?val);?

程序例:?

#include?<stdio.h>?
#include?<setjmp.h>?
#include?<stdlib.h>?
void?subroutine(jmp_buf);?
int?main(void)?
{?
???int?value;?
???jmp_buf?jumper;?
???value?=?setjmp(jumper);?
???if?(value?!=?0)?
???{?
??????printf("Longjmp?with?value?%d\n",?value);?
??????exit(value);?
???}?
???printf("About?to?call?subroutine?...?\n");?
???subroutine(jumper);?
???return?0;?
}?
void?subroutine(jmp_buf?jumper)?
{?
???longjmp(jumper,1);?
}?
??
??
??

函数名:?lowvideo?

功??能:?选择低亮度字符?

用??法:?void?lowvideo(void);?

程序例:?

#include?<conio.h>?
int?main(void)?
{?
???clrscr();?
???highvideo();?
???cprintf("High?Intesity?Text\r\n");?
???lowvideo();?
???gotoxy(1,2);?
???cprintf("Low?Intensity?Text\r\n");?
???return?0;?
}?
??
??
??

函数名:?lrotl,?_lrotl?

功??能:?将无符号长整型数向左循环移位?

用??法:?unsigned?long?lrotl(unsigned?long?lvalue,?int?count);?

?unsigned?long?_lrotl(unsigned?long?lvalue,?int?count);?

程序例:?

/*?lrotl?example?*/?
#include?<stdlib.h>?
#include?<stdio.h>?
int?main(void)?
{?
???unsigned?long?result;?
???unsigned?long?value?=?100;?
???result?=?_lrotl(value,1);?
???printf("The?value?%lu?rotated?left?one?bit?is:?%lu\n",?value,?result);?
???return?0;?
}?
??
??

函数名:?lsearch?

功??能:?线性搜索?

用??法:?void?*lsearch(const?void?*key,?void?*base,?size_t?*nelem,?

???????size_t?width,?int?(*fcmp)(const?void?*,?const?void?*));?

程序例:?

#include?<stdio.h>?
#include?<stdlib.h>?
int?compare(int?*x,?int?*y)?
{?
???return(?*x?-?*y?);?
}?
int?main(void)?
{?
???int?array[5]?=?{35,?87,?46,?99,?12};?
???size_t?nelem?=?5;?
???int?key;?
???int?*result;?
???key?=?99;?
???result?=?lfind(&key,?array,?&nelem,?
???????????????sizeof(int),?(int(*)(const?void?*,const?void?*))compare);?
???if?(result)?
??????printf("Number?%d?found\n",key);?
???else?
??????printf("Number?%d?not?found\n",key);?
???return?0;?
}?
??
??
??

函数名:?lseek?

功??能:?移动文件读/写指针?

用??法:?long?lseek(int?handle,?long?offset,?int?fromwhere);?

程序例:?

#include?<sys\stat.h>?
#include?<string.h>?
#include?<stdio.h>?
#include?<fcntl.h>?
#include?<io.h>?
int?main(void)?
{?
???int?handle;?
???char?msg[]?=?"This?is?a?test";?
???char?ch;?
???/*?create?a?file?*/?
???handle?=?open("TEST.$$$",?O_CREAT?|?O_RDWR,?S_IREAD?|?S_IWRITE);?
???/*?write?some?data?to?the?file?*/?
???write(handle,?msg,?strlen(msg));?
???/*?seek?to?the?begining?of?the?file?*/?
???lseek(handle,?0L,?SEEK_SET);?
???/*?reads?chars?from?the?file?until?we?hit?EOF?*/?
???do?
???{?
??????read(handle,?&ch,?1);?
??????printf("%c",?ch);?
???}??while?(!eof(handle));?
???close(handle);?
???return?0;?
}?
??
??
??
??
?