函数大全(c开头)

韩冰

函数大全(c开头)

函数名: cabs 功 能: 计算复数的绝对值 ' ?# I4 j" p! N" Y用 法: double cabs(struct complex z); 程序例:

#include . b" {0 x+ H0 z( g9 J7 j/ Q" \#include

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int main(void) ) v: b7 n" H* w! Y{ struct complex z; 7 J" T" a! ?' {0 K. }! `double val;

z.x = 2.0; z.y = 1.0; val = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; } : I1 j8 |3 n4 Q$ Y; @9 ?1 \( ^ # k; ^! k- n( F

函数名: calloc 功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); # z! O' u0 l0 l) m8 F7 d程序例:

#include p, j% c2 z& X; Z/ L#include

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int main(void) 5 D( D q4 i6 T. O+ W$ ~3 M8 G{ char *str = NULL;

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/* allocate memory for string */ , J1 r7 `* @1 ~1 X5 y1 ~! s: p' {str = calloc(10, sizeof(char));

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/* copy "Hello" into string */ strcpy(str, "Hello");

/* display string */ 0 ~+ m0 m& {+ i. `4 ~printf("String is %s\n", str);

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/* free memory */ 3 P+ [5 R' J/ v3 R- S7 j! q# ]4 @free(str);

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return 0; }

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函数名: ceil 功 能: 向上舍入 + R! n6 T$ e- s4 W用 法: double ceil(double x); 程序例:

#include 2 m; e I& q6 }#include

int main(void) { ' q* {2 {" M K! c7 z3 e$ \double number = 123.54; double down, up;

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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; 3 l+ H; K7 v# ^, j( ]. ] e& G3 D} . Z3 X1 [: m8 s* l" p ; _3 ]" @( D& ^9 f/ I5 U$ L $ Y% z0 O7 n- D) G- F" o% C6 e5 f

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函数名: cgets 3 z1 K5 o* {" [8 |5 j4 L功 能: 从控制台读字符串 用 法: char *cgets(char *str); * Q8 x* {9 D; j. s7 k程序例:

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#include 7 i3 H: [0 E9 O9 m' H: |#include

int main(void) & z6 x1 H- b' I* l$ ]0 t{ char buffer[83]; char *p;

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

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printf("Input some chars:"); * o0 b( W9 L" xp = cgets(buffer); 0 J& a+ c8 F6 K3 _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;

printf("Input some chars:"); 1 ^* A0 _ B* a2 O! jp = cgets(buffer); - m: _; p A& E7 cprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 4 ^0 s7 M6 O$ p; J/ fprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); % \( w% {/ v& O: xreturn 0; # G' B9 s+ g9 ^, [3 |+ D/ G} 9 r- L6 M& V; S& b% O f; T : ~2 @; [& Z6 L/ J; Y

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函数名: chdir 功 能: 改变工作目录 # k( K! L# h: P# E+ ~用 法: int chdir(const char *path); 程序例:

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#include #include + C0 B" u* w' {2 T- h#include

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

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int main(void) 6 |* B# a4 p3 x{ if (getcurdir(0, old_dir)) 8 o0 Q8 Z6 T; F- d9 G6 \- W2 J{ # F7 X' ?4 F: cperror("getcurdir()"); ( q; J% [5 v% l1 d, ]7 Xexit(1); } printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) ! y+ \. o9 A6 ]! _- S4 ^) S{ : c3 i( f+ s% A; bperror("chdir()"); exit(1); 7 T6 E$ n5 N2 E# b}

if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); ( v4 z/ U u, Z, [# {} printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); # w1 P, |. Q* ^5 ]4 G2 A9 \if (chdir(old_dir)) { perror("chdir()"); 9 O ]5 m5 ^/ D- v7 M- i2 I. ^exit(1); }

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return 0; 8 i- i* K" q. {( S2 y, w; O: e+ X} ; ]) g8 c& m2 b. @/ S

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函数名: _chmod, chmod ) J8 i" _8 R& i% @; [* R功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); / L1 q5 l7 x# Z0 ~* ~* R程序例:

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#include 3 [& P) O6 W8 m4 c#include #include

void make_read_only(char *filename);

int main(void) { 1 m4 ]5 `7 Z" h5 ymake_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); # g3 t5 R6 C7 E( l/ Zreturn 0; ' H4 s& w$ A3 M6 o( k) J}

void make_read_only(char *filename) { int stat;

stat = chmod(filename, S_IREAD); if (stat) printf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); } 8 j3 V9 `, l/ I $ t3 u( N: h: T

函数名: chsize 功 能: 改变文件大小 ! l- X( E. _7 o# V" l用 法: int chsize(int handle, long size); 程序例:

#include $ V3 h: [7 O$ |& U: ~#include #include

int main(void) { & d0 r1 F" X7 P3 [ Yint handle; 5 r7 _# W& T: A/ V' fchar buf[11] = "0123456789";

/* create text file containing 10 bytes */ handle = open("DUMMY.FIL", O_CREAT); write(handle, buf, strlen(buf));

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/* truncate the file to 5 bytes in size */ chsize(handle, 5);

/* close the file */ 9 J$ E- ]. c) h+ w, fclose(handle); return 0; ) |% v# R8 S4 ^: x% b+ F} , p5 \( |( v, T7 Q$ Q* f- ] 8 ^9 b7 H$ Z0 l. }

函数名: circle " d/ Q( j- X, }7 |4 k功 能: 在给定半径以(x, y)为圆心画圆 / ~6 Z6 O y/ v( v1 T$ F6 L3 w用 法: void far circle(int x, int y, int radius); 程序例:

#include 1 A1 u+ ?- ^8 {$ q& l/ W% F#include #include #include

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int main(void) { " w' k" P. j* r2 H) ?. L/* request auto detection */ 6 K/ M( s0 O: ~+ P4 mint gdriver = DETECT, gmode, errorcode; ! E4 _- o! |2 G0 x3 l( }" vint midx, midy; int radius = 100;

/* initialize graphics and local variables */ ) H8 u P: @1 r: x& {7 x- r- B: kinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ' [/ r' b+ V( q m$ v. }/ F" W0 _errorcode = graphresult(); : r5 Z K# o4 `, p; @1 ?0 _; {- ~if (errorcode != grOk) /* an error occurred */ { e. T5 U- ]5 F7 dprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 5 A5 }+ N$ X. K# g: q9 C: }9 eprintf("Press any key to halt:"); getch(); ! C: L! G h. I1 M' h: L9 Texit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; # K+ T% d: P& D% W$ U9 X3 X3 ymidy = getmaxy() / 2; setcolor(getmaxcolor());

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/* draw the circle */ ( f0 ~* ^1 F/ Mcircle(midx, midy, radius);

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/* clean up */ getch(); ( Z2 m" j! S! Y0 Q9 wclosegraph(); return 0; } ; h! F/ U Q( ~& U! s$ q; l 8 R8 a" b2 [2 \& F3 r7 V% n( |; N, w 5 i0 F5 X$ W9 Q3 U

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函数名: cleardevice * n' U' @. Q0 Z# @: ]功 能: 清除图形屏幕 9 x& |7 G+ J1 `! R用 法: void far cleardevice(void); & h6 B2 N m) @! b8 B8 j0 t程序例:

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#include #include . ?% T& y+ v% \. \ G! \3 s' s#include 1 R. W6 ?* e3 B! `#include

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int main(void) { + k! v: p1 `5 j; U, I# h" s: p/* request auto detection */ int gdriver = DETECT, gmode, errorcode; - v! l) i1 K3 A: q( gint midx, midy;

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/* initialize graphics and local variables */ 2 m( j+ G! b; Winitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ % {) b: |/ K8 y2 ~( t( i6 S{ , a/ q' v1 l4 z0 R! ]% J$ qprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; midy = getmaxy() / 2; ' D7 O+ e/ D3 Z2 n; I2 xsetcolor(getmaxcolor());

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

/* output a message to the screen */ 5 H- l3 X7 \" xouttextxy(midx, midy, "press any key to clear the screen:");

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

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/* clear the screen */ cleardevice();

/* output another message */ 4 g5 U; U6 ^' O1 w8 i ?9 _outtextxy(midx, midy, "press any key to quit:");

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/* clean up */ getch(); 7 f4 P' u: m, Aclosegraph(); return 0; ( S9 D: C; R, ^4 |} 0 l; Q" T8 i1 ]2 A _1 a$ j ; {0 A1 l8 Q9 O6 q

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函数名: clearerr 功 能: 复位错误标志 - G9 K/ D+ w# j* o; p i用 法:void clearerr(FILE *stream); , T- o; w3 K: F6 X; c+ ^程序例:

#include

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int main(void) - p, A" q3 ?, w{ + s4 b0 J' w9 _$ C! a0 n: r; @FILE *fp; 1 n+ I% a& F7 n# |. vchar ch;

/* open a file for writing */ % }7 D4 D2 Q$ N" r u; L" G3 Wfp = fopen("DUMMY.FIL", "w");

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/* force an error condition by attempting to read */ ch = fgetc(fp); ' i) s7 z5 W1 Z9 t0 ]6 ]printf("%c\n",ch);

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if (ferror(fp)) 2 @$ Z j) ?7 y{ /* display an error message */ ! c4 e$ @$ y& @/ s7 uprintf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ ) k$ r! _ O0 t1 w5 eclearerr(fp); }

fclose(fp); return 0; } - x- w/ C% E j ! T/ v7 {6 w# L8 ?4 U& T, |% ^- u

函数名: clearviewport 2 d' @- ]/ `2 b6 Z7 q. _' L功 能: 清除图形视区 用 法: void far clearviewport(void); 程序例:

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#include ; @' d# S, Q/ _( F; i8 `#include - L$ Y7 G5 ?) Z9 Y, X( u6 n+ Q#include #include

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

int main(void) ' @9 K; z% I% j' A- V! C5 N% V) @{ /* request auto detection */ 2 q6 b0 I* n% v8 C+ `int gdriver = DETECT, gmode, errorcode; + {2 y% H$ U8 {' S z6 h: qint ht;

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

/* read result of initialization */ errorcode = graphresult(); , c* \: `* M6 r/ K( nif (errorcode != grOk) /* an error occurred */ { % Q; N6 ` u1 R: b( h5 r% q X* @printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); A) B8 \. [$ H. f, f, B( j, K% d9 [exit(1); /* terminate with an error code */ 3 J, D# o/ {1 n8 ]+ G5 Y9 S0 y}

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setcolor(getmaxcolor()); 7 o9 R3 ^* U5 r1 A1 c3 \ht = textheight("W");

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/* message in default full-screen viewport */ 6 M0 F. U5 C% n5 M* t, nouttextxy(0, 0, "* <-- (0, 0) in default viewport");

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

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/* display some messages */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); outtextxy(0, 2*ht, "Press any key to clear viewport:");

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

/* clear the viewport */ ! x* [1 V$ s7 C* Q3 E6 Gclearviewport();

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/* output another message */ outtextxy(0, 0, "Press any key to quit:");

/* clean up */ ; v, n6 d5 z& t2 v$ X5 Jgetch(); 7 `) w7 ~% }2 ], F) W8 J1 pclosegraph(); 8 ?" Z6 B. D9 D" oreturn 0; } % U' R7 A/ }: ~$ \0 X- f0 B2 w ; ^/ [: H4 _$ c. x5 ]4 ?2 c

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函数名: _close, close 功 能: 关闭文件句柄 ' D% k0 ^* S3 r9 z用 法: int close(int handle); 5 w; G6 Z7 q4 ?# e9 C5 u程序例:

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#include " g+ x' F6 E J7 f, M/ p/ F2 s#include ; o/ |& O$ Y0 W0 F0 d3 D+ B#include : }& I- F( b7 Z% r# a& c+ a. Z# J#include

main() - z, m$ `' x& v f1 I{ int handle; + b. P7 d5 T8 c8 Y! ] Dchar buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); ) M7 R, e, i; M; nif (handle > -1) { write(handle, buf, strlen(buf));

/* close the file */ close(handle); } else { * i' @) l3 i, N4 b0 ~9 y7 D$ Hprintf("Error opening file\n"); ; `$ E* Y. i' A2 U L1 p6 i} return 0; } & r& ]: ]7 j* P; m) Z3 a : b7 B' ~4 z' L" U2 f) X. |4 ?

函数名: clock - Z! Z: v* x* G+ Y: `, l( F( g功 能: 确定处理器时间 3 }0 m( G" X" @1 R* t用 法: clock_t clock(void); % f6 T+ H# [ J& Z; ^ K程序例:

#include \7 Q% ^* z$ ?5 n1 p7 [# I( [#include 9 B1 g" L+ f$ ~9 c+ q2 t% B#include

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int main(void) ; W" \, ^# y3 ~$ ^, }% N. D{ clock_t start, end; & l i } [: Astart = clock();

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delay(2000);

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end = clock(); printf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; ' r1 b! j/ s+ }% J# n5 H; D3 e} : H T7 G: M C# g$ ?0 @8 c

函数名: closegraph ( ] K$ o2 ]5 Y. p/ t功 能: 关闭图形系统 用 法: void far closegraph(void); # C- |' p1 y) u% w+ A程序例:

#include 5 ?6 P0 n$ W/ t#include / [5 a; Q- O7 R4 F% Y+ D* z, M#include ) }" V1 {- p9 j, {/ v. p& [#include

int main(void) { 9 H' q) u/ p9 G6 `7 Z, B/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int x, y;

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

/* read result of initialization */ - t$ F1 M' p( T0 J4 Q& _errorcode = graphresult();

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if (errorcode != grOk) /* an error occurred */ { 7 |* G! i9 `. ?printf("Graphics error: %s\n", grapherrormsg(errorcode)); ! b0 ?. }# ]+ Y! S$ `printf("Press any key to halt:"); , v" Y" ]- V/ ? x Sgetch(); exit(1); /* terminate with an error code */ }

x = getmaxx() / 2; y = getmaxy() / 2;

/* output a message */ . S" `3 x k5 z0 F' O0 `+ gsettextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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

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

printf("We're now back in text mode.\n"); 3 ~( I& i% B b- ~: ~ E+ ~printf("Press any key to halt:"); 6 O4 _6 P5 Z# Q. r( [1 Agetch(); return 0; 2 S3 g! ?3 Q) A2 A* U} 7 a2 u% u* H/ D" Y7 D' H 3 y; b7 m" U; x( ]3 t1 ?

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函数名: clreol 功 能: 在文本窗口中清除字符到行末 2 |4 ]. R0 F9 p4 A. { r$ ?% ^用 法: void clreol(void); . r. n6 S% [. ]5 k程序例:

#include

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int main(void)

{ 7 Z, k% e% X" ]% W0 @+ \' Vclrscr(); # L$ B6 i( G/ I0 n: Xcprintf("The function CLREOL clears all characters from the\r\n"); cprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); 8 m7 D9 V6 F5 J6 ~cprintf("Press any key to continue . . ."); 1 Q) A! M# U' fgotoxy(14, 4); , Y( [' f m4 A; M$ Igetch();

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clreol(); getch();

return 0; } 3 M4 n) ]1 @. i' W9 {6 O' M' `1 j

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函数名: clrscr " S; u# ~" }+ N* y) ?: J$ W功 能: 清除文本模式窗口 , u1 \" L, {% p) Z8 a用 法: void clrscr(void); 8 r: j& K4 ]5 w+ |$ G4 Q程序例:

#include

int main(void) ! T! l, l. e2 c# _: h{ int i;

clrscr(); : U6 h" q" D, A* Vfor (i = 0; i < 20; i++) 9 j* b, L9 O' pcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

clrscr(); $ X7 K% ?, h6 k( @) n9 S# Q5 Dcprintf("The screen has been cleared!"); " X0 f, A o& ^- q4 ^# n0 igetch();

return 0; } * c* v* q( @# n+ ~* ~ 0 ]7 a! D, o6 Q' w$ S6 j% P" Y5 P( M

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函数名: coreleft : B: }) Z. W+ q. I- y: P功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); . S3 F+ `7 {' e5 X- b1 \8 X程序例:

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#include " D9 Y" T: p7 ?; l! L- V0 O) Z#include

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int main(void) 5 C5 X# ^! ~: `# s U: [{ printf("The difference between the highest allocated block and\n"); printf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; 8 Y7 n. O8 s0 I" N8 g: R% ^- ^} 3 y% H8 x" x3 {! r5 Y& J5 o

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函数名: cos ) r4 v% M; u8 P/ ?$ t/ ]功 能: 余弦函数 用 法: double cos(double x); 程序例:

#include #include

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int main(void) 5 U3 Y* }9 a% ~6 ^{ ( }% o ~; f6 B2 @3 _( G3 Gdouble result; 9 s0 E. J* g% odouble x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); return 0; $ C% G/ N( k+ u. O) H! `5 J! b} ! ~! P) M* [) C! a8 E' C 2 ?2 b& }2 G0 G

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函数名: cosh * T/ M0 e! q0 [, D; K# n功 能: 双曲余弦函数 . B, g& T% }) ~用 法: dluble cosh(double x); % n; P9 y; O; r7 p' _* ^2 v程序例:

#include #include

int main(void) { & X' s1 u: j+ i0 Xdouble result; , K! g4 Z2 b: b3 M2 h6 wdouble x = 0.5;

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result = cosh(x); ( n& u: @! u. Uprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; + X: t, X( @9 p% T' i( D} + z. Q1 v# x6 K- Q! v/ u3 h 7 Y1 ~4 t! D$ z' |; }% D- p7 p

函数名: country ) G/ t* n2 d+ X9 Q5 u3 z功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); 2 I/ @ x J" W; n1 x程序例:

#include #include

#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); # f" s( B6 ?$ xreturn 0; }

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函数名: cprintf 功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); 程序例:

#include

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int main(void) $ }0 j) W. z+ [{ /* clear the screen */ clrscr();

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

/* output some text in the window */ 3 G. E+ W% o* B' zcprintf("Hello world\r\n");

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/* wait for a key */ ^ M6 Y% Q1 W8 Ogetch(); return 0; } . {) s- ~; { G7 d5 p( U$ [

函数名: cputs 8 A; m, \" U; N! {1 A; u功 能: 写字符到屏幕 用 法: void cputs(const char *string); * U4 j0 I0 c- L& X; h1 A程序例:

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#include

int main(void) { /* clear the screen */ ! @. s5 {) V4 t( Xclrscr();

/* create a text window */ 1 ] L& F- ]- B( A9 J. bwindow(10, 10, 80, 25);

/* output some text in the window */ ( ]3 j0 @ |8 ccputs("This is within the window\r\n");

/* wait for a key */ $ H, O7 f% h# n7 u3 b: [8 S7 \0 Bgetch(); ; s1 \& D) M `2 H5 f; Areturn 0; ! J* z" k5 h& V" R} 4 q) e6 T9 _! i- O ! W' V+ J- U9 T z4 M7 c* e

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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); 程序例:

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#include #include 8 e9 Y0 S1 k7 p0 O# `' Z#include 1 y" _' s' C- i- F2 b# P8 F3 m$ [#include

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int main(void) ! V! O) @. ]: R. C) }9 k; ~{ int handle; ( ]$ c9 O. D6 ]1 [3 `- {char buf[11] = "0123456789";

/* change the default file mode from text to binary */ _fmode = O_BINARY;

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/* create a binary file for reading and writing */ ' M" }" F9 j5 Y( A7 h4 e4 whandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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/* write 10 bytes to the file */ 5 n8 R- r6 A: _' o) y$ Dwrite(handle, buf, strlen(buf));

/* close the file */ % R; M" a3 i! [4 M9 k% _close(handle); return 0; } / t. m( n* B" r" |

函数名: creatnew ]! B+ P- H- Y( ~' c" V' A% O功 能: 创建一个新文件 ) g# \7 K3 w+ P$ K用 法: int creatnew(const char *filename, int attrib); 4 ]% x* @& M0 g# P2 ]: v程序例:

#include . B( K! ]3 m* U' X& K5 a& ?#include #include #include #include

int main(void) : C) S* I' u# y; J{ ; M( p$ k' ~' ]5 K( }; u6 i( r! @8 aint handle; char buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ ! i/ o p: v' ]' C2 I Mhandle = creatnew("DUMMY.FIL", 0);

if (handle == -1) printf("DUMMY.FIL already exists.\n"); else 2 Z, q6 A. |6 @ ?: S, o, [7 L{ printf("DUMMY.FIL successfully created.\n"); 3 K& Q2 i" Z; K$ ?write(handle, buf, strlen(buf)); close(handle); & _" j5 S8 d! j; `. |5 q$ z. t* q/ K* w} ) c- Y6 y1 |- d8 h+ N8 _& i7 preturn 0; * G. i6 G; T3 E2 @8 [" H} 2 }1 n6 F0 E; c, M$ [/ |0 E

函数名: creattemp 功 能: 创建一个新文件或重写一个已存在的文件 8 z" F2 ?7 j; l- \' ~; V用 法: int creattemp(const char *filename, int attrib); * F, [# s0 e9 G程序例:

#include # [& M, X: X5 X1 O, G" h% y#include #include

int main(void) { int handle; / R+ Q1 B: P9 L$ s- t% nchar pathname[128];

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strcpy(pathname, "\\");

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/* create a unique file in the root directory */ handle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); close(handle); return 0; } 1 g4 C5 u5 C# |+ u ? 5 ]4 C: M$ }# X* j- i 4 K+ m# x! R- F' Y) h9 a' C7 M" ~- b2 V

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函数名: cscanf 功 能: 从控制台执行格式化输入 0 _0 j# H3 } e5 ?# W用 法: int cscanf(char *format[,argument, ...]); 程序例:

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#include

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int main(void) { char string[80];

/* clear the screen */ & ^4 a3 d8 c8 n( Z1 J' V& W. ` P+ Hclrscr();

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/* Prompt the user for input */ 3 z) J, B; A: ncprintf("Enter a string with no spaces:");

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/* read the input */ ! A: X! f5 l' S9 y, @7 pcscanf("%s", string);

/* display what was read */ cprintf("\r\nThe string entered is: %s", string); return 0; } ( {( p' \' z- P9 S, q: X% P v& P+ u/ q

函数名: ctime 功 能: 把日期和时间转换为字符串 # e/ P# m" C' y用 法: char *ctime(const time_t *time); 程序例:

#include j. _" ]' T; H$ H" {#include

int main(void) { " U6 x3 v% u' y7 t5 B4 Btime_t t;

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time(&t); 1 o9 P- ` D H: L3 r; nprintf("Today's date and time: %s\n", ctime(&t)); # ]. ~& W* @. \6 f1 P! B ereturn 0; 2 A# G c) O1 W0 }; f( s} 5 y6 U9 c& L. J ( L4 a, j* K& x, z6 N" I / P9 _& ?1 L$ H7 p

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 + U/ ^, G. m$ C% @6 W用 法: void ctrlbrk(*fptr)(void); ( l% _0 [3 j" `4 \, P) F* x! u程序例:

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#include 6 c- l b/ C' d) h& e9 I#include

#define ABORT 0

int c_break(void) L+ W) ^" a3 p$ X{ 9 L; @/ p5 F5 ?8 @) W7 l5 [printf("Control-Break pressed. Program aborting ...\n"); return (ABORT); : h' r5 ]+ S2 q! _: Z" _* E( j9 U1 A}

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int main(void) { ctrlbrk(c_break); for(;;) 8 ^6 \# j' q0 `0 x. v{ printf("Looping... Press to quit:\n"); } return 0; }

zjf

[em49]

谢谢啊

chenlk

有价值！

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

gssdzc

还是感谢分享。。。

hjl19890710hjl

特别感谢