函数大全(c开头)

韩冰

函数大全(c开头)

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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) { 1 I$ @7 I2 P; D: Y% a' `4 D' ]0 Kstruct complex z; double val;

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z.x = 2.0; z.y = 1.0; . @$ \0 ?2 c% ?# A4 Xval = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; }

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函数名: calloc 4 L& }# S% } P7 @- q7 u功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include P) U4 w' m: T8 R% S#include

int main(void) 1 i: b3 ]6 T$ k/ n1 \6 F Y{ ! ^+ d& ]0 A: [4 R7 n+ achar *str = NULL;

/* allocate memory for string */ str = calloc(10, sizeof(char));

/* copy "Hello" into string */ ! h6 t7 m4 R6 v7 y+ @strcpy(str, "Hello");

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/* display string */ ; n4 v& ~% m1 s; S- g& t- S& kprintf("String is %s\n", str);

/* free memory */ & L/ V) O4 h4 V5 ]5 Qfree(str);

return 0; 7 _/ U, F4 A+ S( A# q} ; ~7 b4 T" o/ M" o3 G' @8 h

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函数名: ceil ! c6 e! k. v, v/ L功 能: 向上舍入 % G# Y G, X* L- h Z, l# w用 法: double ceil(double x); 程序例:

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#include ( @- p5 ^" a% y6 i* C#include

int main(void) { double number = 123.54; / y9 D. Z' ~& \! ~8 U7 ?/ E( gdouble down, up;

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down = floor(number); * @ | k5 T1 }3 F3 s9 J% V; n& [$ s6 N. v, Zup = 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);

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return 0; } , h) V) N$ ^+ T& J; y8 G9 o" v

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函数名: cgets ) l. C+ L( S v7 S, r$ {功 能: 从控制台读字符串 用 法: char *cgets(char *str); 6 D' t* j# w; `5 \/ _% @3 d程序例:

#include #include

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int main(void) { + u/ Z% { P5 Echar buffer[83]; char *p;

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/* There's space for 80 characters plus the NULL terminator */ - G) R% _* x( X1 V2 q5 Kbuffer[0] = 81;

printf("Input some chars:"); p = cgets(buffer); 4 B3 L2 h8 C& f3 Tprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer);

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/* Leave room for 5 characters plus the NULL terminator */ + t% V7 Q9 S! | _$ z0 h$ L8 m& bbuffer[0] = 6;

printf("Input some chars:"); p = cgets(buffer); 7 v3 O; R% u/ |. tprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 1 I8 K/ w: H9 [& H& s& C9 hprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); + w8 Q$ }# B$ P& L; ~0 t6 zreturn 0; [8 E! l. o2 Z" [7 q1 k* W7 ^- z} 3 H0 r1 K) e! g, T0 C, D1 ^

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函数名: chdir ( a+ K0 y Z0 H; w3 [% G5 J功 能: 改变工作目录 6 I) H1 x# w, { a3 U用 法: int chdir(const char *path); 程序例:

#include 3 U& D. [$ _' U3 {#include / W4 W& f. \6 q! j. x% Y% i#include

char old_dir[MAXDIR]; 4 x% ~2 n0 R: Xchar new_dir[MAXDIR];

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int main(void) { + t+ N. Y) G c7 r( h: sif (getcurdir(0, old_dir)) $ v1 b' ?* i# x9 }8 f/ ]: Q) q6 W{ 1 `; i2 q! Z- u' w9 l) ` Xperror("getcurdir()"); exit(1); % t3 q, E: a% `& G. m} printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) ' n6 X( b, D& N- y{ perror("chdir()"); ; ^; c6 Z! g5 U+ g# ^/ jexit(1); ' [0 U0 b' c4 F2 v$ b/ p; R1 O0 Y- s}

if (getcurdir(0, new_dir)) { 1 z0 A& o+ j2 [9 s4 q8 M7 |perror("getcurdir()"); exit(1); } printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); if (chdir(old_dir)) { + l' T) b) x6 H7 `" {perror("chdir()"); . X& d& W D5 A+ }: t" s, Jexit(1); }

return 0; - y+ Q4 ~" c0 s8 h# o7 o} : b" p9 H# @: b# |# a- b$ M

函数名: _chmod, chmod : o( @4 I/ o( x L; H$ M& S' F E2 l功 能: 改变文件的访问方式 7 E; q; G3 T; g/ ]0 a6 w: H$ ^/ R ]用 法: int chmod(const char *filename, int permiss); # a6 i# V" k# q0 v6 [0 @程序例:

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#include #include 2 v4 p4 _% C' w+ F# V#include

void make_read_only(char *filename);

int main(void) 2 v$ ~9 y; X& A; W4 Z( r{ / s+ C0 n3 d0 H6 o) Y2 Rmake_read_only("NOTEXIST.FIL"); 8 U/ X! T/ V# v1 Smake_read_only("MYFILE.FIL"); 9 n+ k" g" y. }% areturn 0; }

void make_read_only(char *filename) " {; u0 k/ S1 w. K6 A% x0 L: M2 O{ & K: s7 b$ r! J: y% iint stat;

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stat = chmod(filename, S_IREAD); if (stat) # g, d+ H+ U) Q+ z1 Pprintf("Couldn't make %s read-only\n", filename); else 9 t2 |% N5 r& T+ v& Q# X/ }printf("Made %s read-only\n", filename); 0 |; P3 L- X, v( ]' e8 }& }} ) A# n1 N6 A, I( ? % y# S# l; Q7 i C

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函数名: chsize & O8 z$ g, |0 M, c# x# h功 能: 改变文件大小 ' o, y+ n0 m$ c, T3 _$ H$ Z用 法: int chsize(int handle, long size); 程序例:

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#include 7 ?! q1 n' g# L g9 v( s- n! F#include #include

int main(void) { 2 L1 Y$ E: f' M# a# B F* Sint handle; char buf[11] = "0123456789";

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/* create text file containing 10 bytes */ - _+ E3 b5 l( F1 zhandle = open("DUMMY.FIL", O_CREAT); ) `$ h A2 c5 D) B1 f4 a: ^write(handle, buf, strlen(buf));

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/* truncate the file to 5 bytes in size */ 8 b1 F6 w3 k. Cchsize(handle, 5);

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/* close the file */ close(handle); return 0; : ^ t$ \: D9 S4 k6 n5 m} # S3 d7 {' M) X( y0 d' }/ ]

函数名: circle ; }, U7 N$ t+ b" P& I9 x功 能: 在给定半径以(x, y)为圆心画圆 4 Z) I: _ c ~; t用 法: void far circle(int x, int y, int radius); 程序例:

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#include #include #include / I i8 l9 J. `! g#include

int main(void) # A6 K C2 ~ |" ?4 x3 O3 B# ^0 @7 x! @{ * o; `5 q+ E, k- Z% I/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy; / V" A* C; X. ]6 u& t' Eint radius = 100;

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/* initialize graphics and local variables */ * b1 U j: b5 R+ @; k, |initgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ # [. G1 S8 O# y{ ! V. M. }) k& d% |4 l& oprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); % p$ D0 C( A# Ogetch(); ) I3 H9 O, ^# I+ G7 ^4 Y- Jexit(1); /* terminate with an error code */ 2 h2 n, q: m# ]9 e- u}

midx = getmaxx() / 2; midy = getmaxy() / 2; setcolor(getmaxcolor());

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/* draw the circle */ 2 J. d6 A1 N @) ccircle(midx, midy, radius);

/* clean up */ * M6 P6 r2 `& o7 O% Cgetch(); 2 S( D2 M' d2 H& p: V. uclosegraph(); : `4 T i' @) N0 @- V0 }) preturn 0; } % k: S5 A0 |/ \! W) v |, G) E

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函数名: cleardevice 功 能: 清除图形屏幕 * N {4 d5 Q; h" l8 D用 法: void far cleardevice(void); 程序例:

#include t+ _6 Z2 ?2 O Q/ S#include ( X8 J% u* ~$ Q: Q) n/ }#include ^; T6 `% g; g7 k9 N; u3 t7 I#include

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int main(void) 2 A+ [7 I- |7 r2 F{ J3 S& ~$ ^: B3 m/* request auto detection */ % G" B. B- c( G, ~& `int gdriver = DETECT, gmode, errorcode; + m8 z0 s" ^) N4 cint midx, midy;

/* initialize graphics and local variables */ 7 _2 n3 M' X& D6 X# d* S9 ]initgraph(&gdriver, &gmode, "");

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/* read result of initialization */ " N1 s8 @/ K9 Uerrorcode = graphresult(); 9 _* J4 d+ d( k3 S$ iif (errorcode != grOk) /* an error occurred */ / {0 {3 y, A9 V& u R5 @3 m5 m{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 1 r8 a) @" l) ]% h9 x! C. Fgetch(); exit(1); /* terminate with an error code */ * p: M2 a. u# t7 `}

midx = getmaxx() / 2; midy = getmaxy() / 2; setcolor(getmaxcolor());

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

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/* output a message to the screen */ outtextxy(midx, midy, "press any key to clear the screen:");

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

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/* clear the screen */ + K+ A; E! R' M" l$ |cleardevice();

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/* output another message */ / b4 i9 s; K( s, z4 T; Souttextxy(midx, midy, "press any key to quit:");

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/* clean up */ getch(); 6 g F& J. R N7 @/ l; ^! f" z5 Fclosegraph(); 9 r4 Z: V) G: \return 0; 1 y8 k4 F; l- P3 Z}

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函数名: clearerr 功 能: 复位错误标志 用 法:void clearerr(FILE *stream); 程序例:

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#include

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int main(void) { ' Q) n5 N! E T% oFILE *fp; 8 Y" J0 ^# O# Jchar ch;

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/* open a file for writing */ : J" k5 w1 c& G5 }5 S; y# Z& ?fp = fopen("DUMMY.FIL", "w");

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/* force an error condition by attempting to read */ & [. d( G6 V) l. x nch = fgetc(fp); printf("%c\n",ch);

if (ferror(fp)) { /* display an error message */ 6 ~8 P( }4 x" C4 {$ V3 kprintf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ 2 f5 }" E# I- g& [/ \clearerr(fp); }

fclose(fp); ( R d# k: i0 Jreturn 0; . ~- ^) J1 O3 w+ e} - S2 P! a- e z c7 r6 Z! U3 ]+ m / K; o4 _4 w6 P + p" I7 ]5 ^3 Q! T

函数名: clearviewport 功 能: 清除图形视区 ( F+ E. z# U& T2 @& \& b用 法: void far clearviewport(void); 程序例:

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#include 3 k5 T! R* s' Y( y4 @+ ~# Z) L#include #include #include

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

int main(void) { # w& s! L; s- l' k4 e- w8 F/* request auto detection */ / G( R k+ m' x, Cint gdriver = DETECT, gmode, errorcode; . c N, T' \! c9 Qint ht;

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

/* read result of initialization */ 4 J* l0 b5 P# D& W- Ferrorcode = graphresult(); U+ m$ P, ~ D, i& Jif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); , H4 J% N' {- iexit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); ht = textheight("W");

/* message in default full-screen viewport */ ' V/ f4 S7 S5 h, e! |outtextxy(0, 0, "* <-- (0, 0) in default viewport");

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

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

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

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/* clear the viewport */ clearviewport();

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

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/* clean up */ getch(); closegraph(); 4 s, O3 U; r5 j/ sreturn 0; } 4 d7 |) o' t+ T% S0 } 1 s8 c, X9 {' A8 m& h' q 9 n1 U5 ^$ F, {6 B0 O/ c

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函数名: _close, close 功 能: 关闭文件句柄 7 s6 Q) |# c# n O用 法: int close(int handle); . t4 f% U6 @ Y% s2 E9 Y0 Z程序例:

#include , f( x* c# I7 B/ L! r* |9 G#include 7 o+ Z% u6 K) |8 u6 T @#include 8 F' T5 i$ \$ E6 Q" D6 x7 f) x#include

main() { 9 w! R$ C/ y7 `8 _1 E$ Vint handle; char buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); / l; V$ W8 F9 F" e8 ^0 Sif (handle > -1) + `- b9 S* c5 m4 w2 t$ R{ {+ O( T3 N2 \$ o. N+ nwrite(handle, buf, strlen(buf));

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/* close the file */ close(handle); } else $ F: }- h9 I! ^5 x1 D! l7 f{ printf("Error opening file\n"); } return 0; } $ ?9 d! A6 q6 g! P8 c. q

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函数名: clock 功 能: 确定处理器时间 ) T( n" b* h# ^1 r. r用 法: clock_t clock(void); 程序例:

#include ' J/ |7 L) i8 ^1 ]#include #include

int main(void) { 6 V' a1 E5 U/ @9 h% C3 {+ K* u, b) Gclock_t start, end; % q9 b' O* g/ ^0 Sstart = clock();

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delay(2000);

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

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return 0; } % W% E# j+ ~/ q @8 o- I! d6 }

函数名: closegraph 6 Q0 P; O7 l2 X m/ w功 能: 关闭图形系统 X/ {: k8 b0 g' q+ L用 法: void far closegraph(void); ( ? S$ Y. `+ x8 b, F0 k6 ^0 b5 j程序例:

#include 1 ~4 S1 u6 H: ?( h: s3 g#include 6 |" ]+ f- M+ d. q( R8 v% M#include 0 F9 |) h3 y, t, c P#include

int main(void) { /* request auto detection */ - U, W& f7 @5 M) F# y$ C, S0 Vint gdriver = DETECT, gmode, errorcode; # _* w) P" _. t8 lint x, y;

/* initialize graphics mode */ / p! V6 @% f* Y' v; W( h! E8 Minitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ - l! k; C0 }: @( n; \7 N9 d( Uerrorcode = graphresult();

if (errorcode != grOk) /* an error 1 T% q5 ]7 Z% Foccurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); 5 y: g m" }+ t% Jprintf("Press any key to halt:"); 7 y; k3 a1 _' `" L1 m3 tgetch(); exit(1); /* terminate with an error code */ }

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x = getmaxx() / 2; & _3 M+ E6 c* ?0 }" }y = getmaxy() / 2;

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); 1 w: Z- B/ X# Y' R1 n( F/ J, Houttextxy(x, y, "Press a key to close the graphics system:");

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

/* closes down the graphics system */ 4 {* F* g- W0 k1 m( t8 s! m9 y5 mclosegraph();

printf("We're now back in text mode.\n"); 6 Y) z+ T5 R! T4 {: U! b: wprintf("Press any key to halt:"); getch(); return 0; } & S$ C" A Q) h; r% k% w , }5 E# n. e, V 8 D: {! f V! C

函数名: clreol 功 能: 在文本窗口中清除字符到行末 9 u* S8 F- X- K用 法: void clreol(void); & B: j: ?1 O, X程序例:

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#include

int main(void)

{ clrscr(); 5 Q2 N* l; O7 p8 `; Ucprintf("The function CLREOL clears all characters from the\r\n"); cprintf("cursor position to the end of the line within the\r\n"); 8 Y' {' M3 E- K* ?/ [6 Ccprintf("current text window, without moving the cursor.\r\n"); cprintf("Press any key to continue . . ."); gotoxy(14, 4); 1 a) b+ w9 |% {; F/ o0 {getch();

clreol(); getch();

return 0; } / a3 R5 q2 l _ 3 G# \% k' o- l2 \ |

函数名: clrscr ( j$ q5 I, q0 L& G/ f功 能: 清除文本模式窗口 i( w3 T$ g4 N& r$ {. g* G) G0 Z用 法: void clrscr(void); ! [8 O0 X# @0 u5 D* C& {2 [程序例:

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#include

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int main(void) { int i;

clrscr(); - [2 l/ z0 ~9 G& H7 [ M2 lfor (i = 0; i < 20; i++) cprintf("%d\r\n", i); 4 U' N: I5 ]$ ~, i+ r; d! pcprintf("\r\nPress any key to clear screen"); ) }* C( D, \$ b$ y$ ugetch();

clrscr(); cprintf("The screen has been cleared!"); getch();

return 0; } 2 T; Y7 @% q# n: c( ?

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函数名: coreleft ; r9 l+ W6 p3 Y; m/ y# [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 #include

int main(void) { , X0 U$ J# m& a- o5 y+ T" k" [8 h9 @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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函数名: cos * ]. F3 e1 v3 i: F$ m/ Z# l功 能: 余弦函数 1 o% u) g3 l1 v+ Y3 O用 法: double cos(double x); 程序例:

#include 1 r6 a) p; N1 B, V4 }8 d6 g* X z#include

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int main(void) { double result; double x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); / F2 ^2 D- x- ^5 preturn 0; } . T8 N) w/ h1 \ + K' h3 B: e: }9 _3 O0 T

函数名: cosh 功 能: 双曲余弦函数 用 法: dluble cosh(double x); 4 u3 Q% v" \. c2 {$ R程序例:

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#include #include

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int main(void) Y5 \ a* y) o* x{ double result; double x = 0.5;

result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); ! V/ o: i# O+ u9 Zreturn 0; : j: D$ c8 T$ `5 b5 W} ' d0 e% ]" s4 ]8 e# s- l. ^ / G! o8 n5 R: l1 R0 { K! ]: Y& Q0 ~+ | $ I3 ^; q1 W7 M+ L" x Q

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函数名: country 功 能: 返回与国家有关的信息 7 _3 D) w1 [: s' o) _' r用 法: struct COUNTRY *country(int countrycode, struct country *country); 程序例:

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#include : }4 I5 }# a5 L) h9 d#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); 1 ^# k$ r' J) s. |return 0; }

函数名: cprintf ' x" B1 F! x8 W v: V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

int main(void) / P7 c. @7 r$ f H( O{ /* clear the screen */ $ G8 h# v1 Y9 @) D/ r# D8 @/ w5 W6 kclrscr();

/* create a text window */ % E5 ~$ j! g/ }( ?8 Pwindow(10, 10, 80, 25);

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/* output some text in the window */ ' [% Y4 r t& S. Q, J4 n0 lcprintf("Hello world\r\n");

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/* wait for a key */ + @- l; Q6 C! X, d3 `0 {- {getch(); return 0; 7 c0 [5 |2 Y' N} * @5 `4 O! U2 P 2 h. X: ?$ d! P8 l) \ v6 c7 m/ f) r/ o

函数名: cputs 功 能: 写字符到屏幕 8 q) A' @- [) A7 F用 法: void cputs(const char *string); 3 w) {' ~" Y& p程序例:

#include

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int main(void) ! ~( p3 B) O3 Y, d9 Q B' m5 B{ : n/ y. I, X& t) P) y/* clear the screen */ clrscr();

/* create a text window */ / O* y% V& r; s( v9 L: kwindow(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 */ getch(); , T; F# R7 F7 y( Preturn 0; ) u- B' K* Y5 a} ! T: s% r6 [; H. ]! r& Q) `7 c 6 v9 z- Y A$ c% T: A; x4 v1 g

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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 & y4 N1 J% y' n- Q) p用 法: int creat (const char *filename, int permiss); 0 j* m0 S( e( v. A% o6 \程序例:

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#include #include #include #include

int main(void) - E3 f' z, T1 Z- r8 z! O% z{ int handle; " ]$ t& a& b S# {( nchar buf[11] = "0123456789";

/* change the default file mode from text to binary */ 5 s4 F- _9 `) |7 Z# ~_fmode = O_BINARY;

/* create a binary file for reading and writing */ ' J5 p1 p2 S' D* M2 S! r! Zhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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/* write 10 bytes to the file */ 1 }: D# ^3 G+ _write(handle, buf, strlen(buf));

/* close the file */ 0 E* {) ^7 |3 q4 E# Fclose(handle); / R# x2 [3 _- k G$ J4 nreturn 0; } 8 u& Z [ |2 a- T% ?

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函数名: creatnew 1 b* X i5 h4 B2 z功 能: 创建一个新文件 + {+ M* h7 R9 [& f用 法: int creatnew(const char *filename, int attrib); 2 ^ M8 F4 M9 j4 R程序例:

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#include #include #include #include #include

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int main(void) ; @3 ?1 {+ ]$ e9 @) {" Q2 O{ int handle; / R$ g6 f4 H( f: _2 }% c5 b, D4 Cchar buf[11] = "0123456789";

/* attempt to create a file that doesn't already exist */ , h- u/ w. r$ Q. `: Zhandle = creatnew("DUMMY.FIL", 0);

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if (handle == -1) printf("DUMMY.FIL already exists.\n"); G+ F' E. V* Y* Kelse , K, A8 s; I1 X$ \0 b. g- y5 M; h+ G{ printf("DUMMY.FIL successfully created.\n"); # u; |! W3 ~6 ~6 V& ewrite(handle, buf, strlen(buf)); close(handle); ( n/ s0 X, C* D1 u0 ?8 k7 M} , N! a* d8 H' J4 A. Lreturn 0; }

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函数名: creattemp ' m% o1 @2 \) o/ R T8 `功 能: 创建一个新文件或重写一个已存在的文件 用 法: int creattemp(const char *filename, int attrib); 8 l, O+ F7 U2 Q5 |; ]& J9 W程序例:

#include #include y& H; e* H7 y+ y* U3 n0 l#include

int main(void) { + g0 f- k& ]; P8 @* T) u3 hint handle; char 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); 5 x7 F) v: i4 a1 k' v, Iclose(handle); # O8 |# z& m: p# }3 W% [) w# L, X6 zreturn 0; }

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函数名: cscanf # ~% n* L! G6 | I功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

int main(void) { : Q5 ^: a, r0 T) K3 }char string[80];

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/* clear the screen */ clrscr();

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/* Prompt the user for input */ 8 m+ q" L7 Q6 g( i4 [6 Mcprintf("Enter a string with no spaces:");

/* read the input */ cscanf("%s", string);

/* display what was read */ . A! N2 t0 G, c, h8 Y% x# Kcprintf("\r\nThe string entered is: %s", string); & ?- c4 s8 e% a# Z- N( m1 @* \return 0; : D K) @! i% N: a, u5 }# j% o} / `* {) n( e, j! p J+ t/ C& D 2 Y2 F$ ]) h. }3 r |6 n 8 Y3 G9 F9 l2 P M# S! X& n

函数名: ctime 9 i5 ~2 Q, W0 n4 b0 b2 u, }功 能: 把日期和时间转换为字符串 # U9 X' ~0 k+ |2 N% q0 m7 R用 法: char *ctime(const time_t *time); # \3 X; a& }1 n/ _3 E程序例:

#include #include

int main(void) / W0 `7 C& b! M) F7 t9 T{ time_t t;

time(&t); printf("Today's date and time: %s\n", ctime(&t)); 2 ?- P7 `: a* U+ c; n6 Wreturn 0; } : {1 j! J/ x% m5 L; I 8 t# Z9 Q/ B0 o : w* f1 t# K' G. A5 a' o0 T: V

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 程序例:

#include #include

#define ABORT 0

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int c_break(void) % i7 V, n: j) a{ printf("Control-Break pressed. Program aborting ...\n"); ; G$ x- e4 X, V, treturn (ABORT); : e8 J5 Z- `3 C}

int main(void) { ctrlbrk(c_break); for(;;) { 3 h9 z- q( L( k ?( C: |- n+ gprintf("Looping... Press to quit:\n"); 9 k/ U& d( E R9 b6 x8 J% s. Y0 ^. ^+ @7 H} G! p# R1 b* F6 k7 B" H# areturn 0; . U7 q* R$ U$ p7 i0 |2 L5 }}

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