函数大全(c开头)

韩冰

函数大全(c开头) / a+ E$ g d( t5 o

函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); * h+ C* @+ ?; B5 z j# s$ y" g程序例:

#include #include

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int main(void) { ! }# ?4 `% o2 B4 l2 w5 Pstruct complex z; ( }4 _. O7 t- k# kdouble val;

z.x = 2.0; " v; Y+ G$ T$ q, X" ~z.y = 1.0; val = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; 6 n- I6 C0 v' {# W( l' P) y% \} 5 Q8 j' a1 J2 t$ |; D* o. l

函数名: calloc & Y2 }/ D2 e4 P- T. l功 能: 分配主存储器 + {0 Q) P' H+ l- F9 v用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include #include

int main(void) 4 b4 t: ?" z/ Z. O{ char *str = NULL;

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/* allocate memory for string */ ! V. U& X2 ?: E& N: lstr = calloc(10, sizeof(char));

/* copy "Hello" into string */ 0 }6 z* G/ W4 Y% }strcpy(str, "Hello");

/* display string */ printf("String is %s\n", str);

/* free memory */ 2 i7 D0 D, e7 K4 U1 ufree(str);

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return 0; } ; \# z# r$ c1 z' z3 Z # s. L: l, w1 Z! O: x

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函数名: ceil # f" }) u- K6 ?/ M# f6 `功 能: 向上舍入 用 法: double ceil(double x); 6 H5 s! ^2 r0 s6 J程序例:

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#include #include

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int main(void) 6 L" m/ Q( u& t{ 6 ]3 ?! o5 k# wdouble number = 123.54; double down, up;

down = floor(number); up = ceil(number);

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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; * t$ H: ^/ z- C$ y2 ^! _+ v& A( L# V} ( l! b% [2 U: i0 F( a4 Y8 f5 q

函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); 程序例:

#include ' N% a& e( Q. |# I#include

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int main(void) { char buffer[83]; char *p;

/* There's space for 80 characters plus the NULL terminator */ buffer[0] = 81;

printf("Input some chars:"); p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer);

/* Leave room for 5 characters plus the NULL terminator */ buffer[0] = 6;

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printf("Input some chars:"); ( M0 r% g: \& C* S. n( ~# ~p = cgets(buffer); : i+ T" U0 h' e/ \9 c! ~: fprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); $ u) |3 e F- I' U3 h# Lprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; 9 ~9 O) K8 d2 C2 e} 1 S- d" t$ s; a, U [% g$ F/ h0 ?4 C

函数名: chdir - F# A" r- Y& [功 能: 改变工作目录 " Z3 A$ x5 v7 ]) ^用 法: int chdir(const char *path); : z, C3 x) }3 q! w8 d, A% Y程序例:

#include 7 v- o3 P* n# L# V#include #include

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char old_dir[MAXDIR]; char new_dir[MAXDIR];

int main(void) 9 k) q' Q) o% I! |- e{ if (getcurdir(0, old_dir)) { perror("getcurdir()"); exit(1); } / K' F* x3 D: {! kprintf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) . h' l& @, C- J5 I3 U{ perror("chdir()"); exit(1); }

if (getcurdir(0, new_dir)) 7 X6 L1 |. \- v" T9 C2 h{ perror("getcurdir()"); exit(1); } 7 ?8 A$ v- j! H" N4 [6 @ xprintf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); 1 h0 z8 k8 W# K; l3 bif (chdir(old_dir)) X3 T8 p9 j# W- B* |* j{ perror("chdir()"); exit(1); }

return 0; 8 {+ }/ a( G. N0 B} & x" `! g- w0 `0 I8 B7 e ) C' v. _* Q% n* D6 s1 p

函数名: _chmod, chmod 功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); 程序例:

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#include #include #include

void make_read_only(char *filename);

int main(void) 7 G8 d$ }. j, [7 w$ X{ 0 C$ q' }! E F x, w9 {make_read_only("NOTEXIST.FIL"); - a; p- ~* r( B6 o7 a3 }2 R8 cmake_read_only("MYFILE.FIL"); : B+ c" b: X" L) ?8 K' I M; Mreturn 0; }

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void make_read_only(char *filename) $ N4 V. r- P! j; G; k6 U( P{ int stat;

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stat = chmod(filename, S_IREAD); # u# N8 O1 h# S$ Aif (stat) printf("Couldn't make %s read-only\n", filename); else ! Z7 V6 M* q1 G7 L/ f5 j$ Q/ y) A9 [printf("Made %s read-only\n", filename); M% z9 s. l% Z& B2 P} 3 e% T& u( s% L6 V% U! d9 [2 D" W2 R + w- w3 g' N* P* K3 V3 a9 ~3 E

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函数名: chsize 功 能: 改变文件大小 用 法: int chsize(int handle, long size); + K; {* }$ t) ]4 T8 l* o程序例:

#include & @. F1 J ]1 n9 C# n- G#include . y- L! Q* [7 q8 S& M( I#include

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int main(void) { int handle; char buf[11] = "0123456789";

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/* create text file containing 10 bytes */ + S U- c4 W: }) m$ ~handle = open("DUMMY.FIL", O_CREAT); ; a' P7 H' c+ r L: f+ ?write(handle, buf, strlen(buf));

/* truncate the file to 5 bytes in size */ " ?! F/ ]" D) l; M1 h, p* N$ Echsize(handle, 5);

/* close the file */ 1 t4 ?8 g7 o4 Qclose(handle); ( p$ K t* K& M. Treturn 0; } . N2 i' H6 |+ _6 _! Q& { $ f7 v" P* ^% ]0 [; ?

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函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 用 法: void far circle(int x, int y, int radius); 3 `& d9 v/ }0 B程序例:

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#include 3 X8 P& a. V! y$ x' u# L#include # x1 U2 l/ O* A5 i#include + N+ I% u* v9 u7 ^#include

int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy; int radius = 100;

/* initialize graphics and local variables */ initgraph(&gdriver, &gmode, "");

/* read result of initialization */ 4 n, x; U$ o' Z' M+ werrorcode = graphresult(); , u2 C( }) E I5 ^3 ?if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); * F2 G2 Z% n' _! J1 ]printf("Press any key to halt:"); getch(); 2 X. c& J; t" x" Zexit(1); /* terminate with an error code */ 2 u% v4 F4 L: z6 d5 Q}

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midx = getmaxx() / 2; % N' V; [/ c% }8 xmidy = getmaxy() / 2; , _& o5 l' t$ z" F) n& l Nsetcolor(getmaxcolor());

/* draw the circle */ circle(midx, midy, radius);

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/* clean up */ * q6 Y) a' F. n5 d- J& i( y7 zgetch(); closegraph(); return 0; } 4 g0 d" |! n6 a# [4 f* W6 M X3 D9 @9 k$ }/ q+ `( U* z 5 f$ w5 x9 @3 H+ N4 |

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函数名: cleardevice 功 能: 清除图形屏幕 ! T+ }/ i- |9 @8 A. D* O7 p用 法: void far cleardevice(void); 2 f( w+ m2 |7 Z程序例:

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#include #include 4 g8 V2 R- k# i7 t% q#include . k3 n7 ?2 u6 V3 x# W* ]#include

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int main(void) { /* request auto detection */ 0 [/ W2 O. H2 w% m* d6 w* V. Jint gdriver = DETECT, gmode, errorcode; . u& _6 V! p" ?1 lint midx, midy;

/* initialize graphics and local variables */ & i& x! [# e% V/ {/ Linitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ ( ^1 S: x V* [' z* Aerrorcode = graphresult(); - m: E$ I5 |' @2 O- b$ Nif (errorcode != grOk) /* an error occurred */ { ! C1 D; s/ U" ]. pprintf("Graphics error: %s\n", grapherrormsg(errorcode)); . H: T. ~* ]9 k2 F( j9 qprintf("Press any key to halt:"); . K2 v9 j6 l, `getch(); 0 w" t3 L/ d3 i+ y' r6 Eexit(1); /* terminate with an error code */ 4 |5 W }/ c2 T$ `! e+ T}

midx = getmaxx() / 2; midy = getmaxy() / 2; + \, x# s9 e0 R% Q) Wsetcolor(getmaxcolor());

/* for centering screen messages */ settextjustify(CENTER_TEXT, CENTER_TEXT);

/* output a message to the screen */ * X& ]. w+ F# d! x* q9 i ?outtextxy(midx, midy, "press any key to clear the screen:");

/* wait for a key */ getch();

/* clear the screen */ cleardevice();

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/* output another message */ outtextxy(midx, midy, "press any key to quit:");

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/* clean up */ getch(); closegraph(); 4 I3 l; s, e# R; I3 j1 dreturn 0; } * j: j8 T2 O) D$ ]4 h & Q1 g- x/ N9 A3 @. I6 N

函数名: clearerr 5 ~+ I$ o, ~, m3 `! \功 能: 复位错误标志 用 法:void clearerr(FILE *stream); 程序例:

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#include

int main(void) . z8 d5 V V. E7 a{ 1 Q; G! s" i. J; r" @2 A" D: w; BFILE *fp; char ch;

/* open a file for writing */ fp = fopen("DUMMY.FIL", "w");

/* force an error condition by attempting to read */ & {: L9 a+ _2 d; [( ^9 ~ch = fgetc(fp); ) ^! s; d7 \1 X: U- T, mprintf("%c\n",ch);

if (ferror(fp)) ) ?) s- Q/ X Y{ /* display an error message */ 7 K* V/ ?) D' D4 y6 hprintf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ % W* H0 d; W/ F' i5 l" a9 }5 B2 Qclearerr(fp); b6 [) m8 @! x/ U5 y. m" C}

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fclose(fp); 1 t5 P( k1 |0 {/ F; Xreturn 0; ) v1 J& Z$ |' c} ' h0 O$ k. Y/ N* Y/ X6 t3 U & W Y9 f. I7 {

函数名: clearviewport 功 能: 清除图形视区 a, F# M" s+ J" A7 Z1 t用 法: void far clearviewport(void); 0 h- \( L* J8 ?1 r6 D' e程序例:

#include . T5 k7 A$ r0 h3 r#include #include J% c) j0 J' W* A#include

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#define CLIP_ON 1 /* activates clipping in viewport */

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int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; # q- }% m; B3 M# w9 v3 J8 Y# Jint ht;

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/* initialize graphics and local variables */ initgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { : l, s7 _5 F: f* Y: d6 p( u* @printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); ( D; l7 |. i+ Bexit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); 5 A; q/ \# b2 q+ m1 Bht = textheight("W");

/* message in default full-screen viewport */ outtextxy(0, 0, "* <-- (0, 0) in default viewport");

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/* create a smaller viewport */ setviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON);

/* display some messages */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 5 n9 Q& }# M# Qouttextxy(0, 2*ht, "Press any key to clear viewport:");

/* wait for a key */ : {' x" k5 I3 C1 q; u* {9 g4 _getch();

/* clear the viewport */ clearviewport();

/* output another message */ - q5 Z1 W9 C4 E4 ^1 b4 Jouttextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); ( |! x% \! k6 f, Q5 T! oclosegraph(); / p" z$ |1 W: b2 c( S- e# N0 hreturn 0; 6 w: ~* _7 @) j$ `} 7 }3 ^. e) m6 i3 W( ~0 ~; l 4 t4 i% s& {- G' p1 e; B ( x5 Z6 y8 o2 G5 v8 M# }

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函数名: _close, close 功 能: 关闭文件句柄 用 法: int close(int handle); . n y! {# S5 Q% _, b程序例:

#include / F' S7 V1 }+ D7 n7 V- o* K#include #include #include

main() # n9 u1 |3 ? J3 s+ V{ + e: n' R0 @* j; G- A1 a# `# p' qint handle; 5 ^/ K, R7 {# x8 y4 ~8 f9 s8 _char buf[11] = "0123456789";

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/* create a file containing 10 bytes */ 9 X& I$ o& Z/ D8 F" ?8 phandle = open("NEW.FIL", O_CREAT); 5 s3 @$ U0 w( F5 @0 j- g& f$ uif (handle > -1) { write(handle, buf, strlen(buf));

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/* close the file */ / r9 v3 v/ A4 bclose(handle); ) a( D& D- x5 d6 `. |} else { " a+ q8 W5 P1 k2 \# d1 Gprintf("Error opening file\n"); } return 0; 3 c+ u& n f. b, c" a" ]} 0 }) U! j9 d4 E) u' y, H

函数名: clock - z* a' j* i4 A4 }0 f功 能: 确定处理器时间 用 法: clock_t clock(void); 程序例:

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#include ) \% ^, g# B% j6 \; Y, y" }5 d#include $ i/ c3 ^& w' ?! \#include

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int main(void) / d, U8 c' g' H0 j/ v3 E{ clock_t start, end; start = clock();

delay(2000);

end = clock(); 1 H- \ a6 G5 @2 f5 pprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; ! p) m: {3 K& a8 Y1 I} 2 k3 O3 a; J0 v$ j+ _

函数名: closegraph 功 能: 关闭图形系统 ) R3 [+ v5 w( y用 法: void far closegraph(void); 5 x7 b8 E a2 m程序例:

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#include #include #include #include

int main(void) { /* request auto detection */ + _" Z8 q. L- T7 O! i' C0 Uint gdriver = DETECT, gmode, errorcode; 2 h, ~6 Y: G1 O) {" T3 C: v- T- jint x, y;

/* initialize graphics mode */ initgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult();

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if (errorcode != grOk) /* an error 6 H4 N, y$ j/ t3 Aoccurred */ 8 O( t% b" T% ~8 L0 c5 p4 y{ 3 f' [$ x# U. m1 T6 o) J$ Jprintf("Graphics error: %s\n", grapherrormsg(errorcode)); ) \( p5 ]% Y% o5 l0 ~printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

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x = getmaxx() / 2; 7 ~6 w) z( ~+ ?: ]1 a0 k* d, qy = getmaxy() / 2;

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/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); * b: q9 m3 @; @6 Pouttextxy(x, y, "Press a key to close the graphics system:");

/* wait for a key */ , }9 Y l& |3 q2 w+ ?& [- }8 Ggetch();

/* closes down the graphics system */ closegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); 4 q' s5 X6 N, R; cgetch(); return 0; } # P5 G1 B4 M9 N2 i7 G3 G; ?

函数名: clreol 功 能: 在文本窗口中清除字符到行末 1 C# f7 T4 I! r) K% d4 |' `用 法: void clreol(void); 程序例:

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#include

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int main(void)

{ clrscr(); , x* O9 Z4 k/ ^0 d+ Bcprintf("The function CLREOL clears all characters from the\r\n"); & Q% N0 D3 |. s& v+ ycprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); cprintf("Press any key to continue . . ."); 0 Y( M) r9 W/ a1 Z% ugotoxy(14, 4); getch();

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clreol(); getch();

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return 0; 5 w5 j, h* f, f; E; Y4 R} ( R# g) s/ J6 r4 @) Q

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函数名: clrscr 功 能: 清除文本模式窗口 用 法: void clrscr(void); 程序例:

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#include

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int main(void) % V1 j9 U3 I3 W X5 Z{ int i;

clrscr(); : V9 c' c' _0 ]5 efor (i = 0; i < 20; i++) cprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); " s4 W8 D7 {, cgetch();

clrscr(); cprintf("The screen has been cleared!"); % G: t0 y/ i7 Y2 w% W# D R8 ogetch();

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return 0; ( j! x& s1 T4 R# i# [} . F) `4 W% @5 T3 `4 W # A( h' y4 n* j4 J7 u% v, \# ~2 r! h 9 [; L/ G% w! {! B( a7 v6 g7 o

函数名: coreleft 功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); 程序例:

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#include ) k/ @# B+ }1 N9 I- A8 f#include

int main(void) / w/ Y, G1 L& ?, V9 Q" h{ / z, [9 u0 S) A3 Wprintf("The difference between the highest allocated block and\n"); : C0 C7 ]9 L3 cprintf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; 3 k- i0 h) P* a: E5 S}

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函数名: cos 功 能: 余弦函数 用 法: double cos(double x); 2 e7 w& j! i3 W, |6 [程序例:

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#include ) b4 ?7 X' C. q, e1 R* h#include

int main(void) { double result; , v4 D2 C* I% Y8 S' Tdouble x = 0.5;

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result = cos(x); , g6 {% I# Q( F7 I# l' ~1 Mprintf("The cosine of %lf is %lf\n", x, result); + g9 m- e' U1 Q$ b- X9 q8 zreturn 0; ' N( w' b5 u$ K, T4 ^} . v0 g; t( T% L) d5 `7 d" o' H 9 a& b3 d4 ?/ i \: f7 _

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函数名: cosh 6 H% P3 \1 s( j6 l l2 ~功 能: 双曲余弦函数 ) q9 ]+ g; o4 N6 B0 m7 Y用 法: dluble cosh(double x); 9 T1 t! t# e6 {& G' a* }程序例:

#include ( c4 n/ r+ \1 u! F# q, _#include

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int main(void) : c/ ?9 S L, t' ^, ?9 C! n+ s0 `{ ( `& w/ L! v. ]3 A0 A% X6 Tdouble result; ; [7 X- g9 d+ Ndouble x = 0.5;

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result = cosh(x); 9 O1 l. Z/ y! kprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; 0 [: V4 J6 g6 ?0 W( j} 5 a7 Y2 w. f Z( }) p: S3 l; F$ o+ d% d

函数名: country $ F/ n# M' O3 N& _/ ~功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); 程序例:

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#include ; N |5 O) j/ O+ n' s#include

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#define USA 0

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int main(void) { struct COUNTRY country_info;

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country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", country_info.co_curr); return 0; # J& w: q: |8 ]5 ? a3 H' Y} 0 B) @2 c: }$ G1 B) {6 b" x3 A1 [

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函数名: cprintf + B- L6 M0 y# ^* [1 N' T功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); 程序例:

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#include

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int main(void) 4 N* M4 a) F' E+ Z3 Q5 \; R{ / ]0 n* t5 D+ c5 x2 n* b# v4 B v/* clear the screen */ 2 `" ~2 I( p3 G$ C4 y& s4 Tclrscr();

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/* create a text window */ window(10, 10, 80, 25);

/* output some text in the window */ cprintf("Hello world\r\n");

/* wait for a key */ getch(); return 0; % N* q; W( _0 m# i/ g* ]} ) V7 p! q# Z3 J7 q4 _/ Y ' e8 Q, A8 ^2 Y. m. p; f x* h0 |6 J

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函数名: cputs + C6 l- N* N* b功 能: 写字符到屏幕 用 法: void cputs(const char *string); " A. f9 N$ O6 L5 z* M- x程序例:

#include

int main(void) : `' P8 h5 x6 z, _, ?{ /* clear the screen */ clrscr();

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/* create a text window */ . D. \0 x) K! _, Vwindow(10, 10, 80, 25);

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/* output some text in the window */ cputs("This is within the window\r\n");

/* wait for a key */ / V( y4 Z# ?1 Jgetch(); return 0; * h9 S# I) ?2 u2 ]7 G/ G} 3 x4 {! E* C3 X" y- l B, y9 F1 @( M

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函数名: _creat creat 功 能: 创建一个新文件或重写一个已存在的文件 用 法: int creat (const char *filename, int permiss); ' T" Z% `. [, r& ]8 a4 w, a, Z8 v程序例:

#include #include % _; J& p/ b, j X$ {0 _- [8 ^#include #include

int main(void) { 0 S% \8 b' U+ T; F5 \* T, Dint handle; ' G8 h% N; Y' K0 R$ [char buf[11] = "0123456789";

& T" `0 c7 \1 c" a" c; {

/* change the default file mode from text to binary */ # [+ b5 E7 c* q0 r1 i% U_fmode = O_BINARY;

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/* create a binary file for reading and writing */ " T0 k3 B7 x6 W+ Whandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

/* write 10 bytes to the file */ + U5 f4 Y, E6 j7 ?write(handle, buf, strlen(buf));

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/* close the file */ close(handle); 7 N9 M; p6 x# l/ j3 Ureturn 0; }

函数名: creatnew 0 e6 [7 r5 m6 y0 S6 H# B* e功 能: 创建一个新文件 , d6 @0 \0 Z3 s W5 `8 Q用 法: int creatnew(const char *filename, int attrib); 程序例:

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#include $ A5 E9 M/ e# r5 Q+ H! Q#include #include / N% c) X, X1 d+ |2 K#include #include

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int main(void) ' v" w& i$ Y( [; Y& ?) E' s/ z' `" E{ int handle; ( x+ a5 G0 N! A+ a/ rchar buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ / y* D7 F( Q( x0 q- G! O2 Y' chandle = creatnew("DUMMY.FIL", 0);

if (handle == -1) 3 i) x, z4 |; |5 G4 p0 sprintf("DUMMY.FIL already exists.\n"); / _" [0 [. S* Lelse * h5 q7 \2 d& M* s{ printf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); 3 }. b1 S; q9 M- `close(handle); & z8 D3 v. x* i} 9 Q4 a0 ^. P+ I! h7 f$ Wreturn 0; } / G0 o6 H8 \$ \) t6 c& k: _6 f; i

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函数名: creattemp y* L( S" D# A功 能: 创建一个新文件或重写一个已存在的文件 * ^: Y+ k6 Y0 G9 }: c k7 [用 法: int creattemp(const char *filename, int attrib); 7 u% h6 b6 C8 P7 O5 V程序例:

#include 4 ]; z' O. \* i( E#include * Q: C# O# |* o0 S4 M#include

int main(void) { int handle; char pathname[128];

strcpy(pathname, "\\");

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/* create a unique file in the root directory */ ! ]% {5 }) d \( G/ Fhandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); close(handle); return 0; } 4 [0 r' r$ d2 r3 u0 M t

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函数名: cscanf 功 能: 从控制台执行格式化输入 6 n% y9 Y# w& z2 P1 I/ s7 o用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

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int main(void) 7 J3 v" A% V* x{ f/ J5 O0 k6 wchar string[80];

/* clear the screen */ clrscr();

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/* Prompt the user for input */ 5 \/ l6 o9 h7 b+ Tcprintf("Enter a string with no spaces:");

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/* read the input */ 9 J: X. s6 N. l( | jcscanf("%s", string);

/* display what was read */ cprintf("\r\nThe string entered is: %s", string); return 0; } ; V9 F) y6 p/ i9 p% M. r" w; j8 c% [ 0 P% c. T2 V$ a& f! X6 d

函数名: ctime 功 能: 把日期和时间转换为字符串 5 ^+ D! H3 a1 V0 O' @# v5 @用 法: char *ctime(const time_t *time); 程序例:

#include #include

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int main(void) { time_t t;

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time(&t); printf("Today's date and time: %s\n", ctime(&t)); return 0; } ( y( q& J( f9 @. \& f 4 j7 f) l6 Y* C- J G. ` Y% I - l# Q9 ?' }1 M4 ^

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 ; K" {! i% x1 V0 Y O! U" M用 法: void ctrlbrk(*fptr)(void); " m. O2 p3 e7 a+ T: [程序例:

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#include #include

#define ABORT 0

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int c_break(void) { printf("Control-Break pressed. Program aborting ...\n"); : Y6 K$ Y3 p0 ]0 }- A( _0 Ureturn (ABORT); }

int main(void) 3 }. L& @. S, X2 R; b2 B{ ctrlbrk(c_break); for(;;) { . U5 Y+ \3 J' x, E* u0 |printf("Looping... Press to quit:\n"); } ; L9 W p, U: e, d! I' a% ireturn 0; 8 t7 b$ _7 x: h J+ G ?) t! |, Q K}

xxb1922

这样看太痛苦了，还不如去下载一个专门查函数的软件，我就有一个

xxb1922

这样看太痛苦了，还不如去下载一个专门查函数的软件，我就有一个

zjf

[em49]

谢谢啊

chenlk

有价值！

gssdzc

还是感谢分享。。。

hjl19890710hjl

特别感谢