函数大全(c开头)

韩冰

函数大全(c开头) . y% }2 f. j( |* p

函数名: cabs / O+ @8 e! n. d k- M) A' [: j功 能: 计算复数的绝对值 6 e2 M1 }. r5 [) S" B用 法: double cabs(struct complex z); ' s ~, } q. J8 W程序例:

#include #include

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int main(void) { + r5 L2 @. `. \3 R1 z8 Hstruct complex z; 0 `* |: z* H' qdouble val;

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z.x = 2.0; z.y = 1.0; Z8 V: Y# z( l* zval = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); 1 W4 H& E! r$ sreturn 0; 8 \$ B) ^) ]) W} 6 y7 d( [9 n0 d

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函数名: calloc 9 f( F* h+ n3 P1 A6 B% g9 l功 能: 分配主存储器 3 ]2 W# i( i: }' Z7 X用 法: void *calloc(size_t nelem, size_t elsize); + e4 O+ [& C5 A K程序例:

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#include 7 k1 ]' D, M' O9 L) S#include

int main(void) 2 ?( q' S. |2 M# F1 T, B0 Y* }; ~{ 6 b8 r7 O( a% m. p& ^char *str = NULL;

/* allocate memory for string */ ) _0 S. L0 E( w: p4 G" y8 ^str = calloc(10, sizeof(char));

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/* copy "Hello" into string */ " k9 N. x$ a* Z5 g& E1 k) V9 d' Y! s Ystrcpy(str, "Hello");

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

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/* free memory */ free(str);

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return 0; , o) q/ K s& m4 I! u. Y7 W3 g} 9 D1 ^, n: L: i6 e 0 K D3 |0 U/ ^

函数名: ceil 功 能: 向上舍入 用 法: double ceil(double x); 程序例:

#include #include

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int main(void) { double number = 123.54; 5 {1 v$ n% `" u: M7 a+ U' W. pdouble down, up;

down = floor(number); + ]( T; p* D5 \+ t; gup = ceil(number);

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printf("original number %5.2lf\n", number); 3 ?- E' l) ]$ B. U' E. W6 ]printf("number rounded down %5.2lf\n", down); printf("number rounded up %5.2lf\n", up);

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return 0; } 8 l# {0 l0 {# S

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函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); : S2 A, S& f7 X4 l T程序例:

#include #include

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int main(void) { # g2 [: d* W" o7 X6 t1 }char buffer[83]; ! q2 z/ m" a" L5 Tchar *p;

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

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printf("Input some chars:"); 8 W0 ~4 q( m- I; Y0 N: Xp = cgets(buffer); 5 y: b) I2 b3 {printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 9 n) r+ ^4 O+ G/ }% p. h$ Cprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer);

/* Leave room for 5 characters plus the NULL terminator */ " j3 K" o5 Z* _$ T% ~" ^& B- lbuffer[0] = 6;

printf("Input some chars:"); p = cgets(buffer); 7 r+ W5 S8 z/ w" p6 t7 `printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); ' d/ ]! b" _, Mprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); 7 k" t+ j+ ?1 |# A- oreturn 0; } 6 m5 S7 r! {) O6 K: K' T

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函数名: chdir : U1 |4 C) R( W7 z9 @$ E功 能: 改变工作目录 用 法: int chdir(const char *path); 9 K: X6 p- o* Q6 L, Z. y程序例:

#include 1 e v8 y; T0 k8 j6 U# X: O+ T1 E#include #include

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char old_dir[MAXDIR]; ; @7 \6 m# M1 Y' t6 \char new_dir[MAXDIR];

int main(void) { if (getcurdir(0, old_dir)) { : D; f: c+ m6 P! ]$ o, ?perror("getcurdir()"); exit(1); } ; Z/ s$ e3 d9 e- t* Gprintf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) { perror("chdir()"); exit(1); ; F9 p. |8 u8 J}

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if (getcurdir(0, new_dir)) { , ^5 F% S: p' M$ k* F d) Gperror("getcurdir()"); / D& O4 j5 \( g: U" dexit(1); # f: R. S7 U) b6 _# t} printf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); if (chdir(old_dir)) { 6 r/ X+ T x' V$ Wperror("chdir()"); exit(1); , T5 W* x2 _! Y2 i7 Q* T}

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return 0; } 0 a, x5 Z) J4 {5 |% m& t* F: h

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函数名: _chmod, chmod 0 e" C* ~# p1 u2 O. q功 能: 改变文件的访问方式 - h! Q5 C! t Q b用 法: int chmod(const char *filename, int permiss); 程序例:

#include 9 }( ~. B* x% G/ I9 W( |+ _#include ' L6 _& [0 X: K/ q3 u/ O$ S3 {8 a& v#include

void make_read_only(char *filename);

int main(void) 8 F2 {0 U% \: z- A8 J{ X5 A G( W2 z* D3 y K1 ]; Gmake_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); 3 V0 C8 p) K0 L! d4 `+ V. p2 yreturn 0; K6 I" F2 J8 b5 i}

void make_read_only(char *filename) 6 N+ B# e# |. ?{ 9 n& l+ X5 ? [3 o3 m. {int stat;

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stat = chmod(filename, S_IREAD); ; T2 f+ d; |3 U1 Bif (stat) " x* l$ h. s' {. H! g6 m. wprintf("Couldn't make %s read-only\n", filename); ]* h" i* s8 P2 t4 f7 @& o# G7 Telse printf("Made %s read-only\n", filename); } 3 O7 u' R4 A7 D+ b1 W

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函数名: chsize 功 能: 改变文件大小 + @1 ?8 x0 t' b# E6 F0 c6 D8 l- Z+ C用 法: int chsize(int handle, long size); 程序例:

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#include #include #include

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int main(void) ! s# W# [1 W" ^& }1 `{ int handle; , U0 t6 Z" B- ~7 I- d" u8 Xchar buf[11] = "0123456789";

/* create text file containing 10 bytes */ & n X2 z% G* _) Ahandle = 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);

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/* close the file */ " n# P* C3 }; s# G) p" e8 N0 gclose(handle); 8 Q* M7 C. R+ a; freturn 0; } $ ]0 M. P! U6 h* ?2 y9 r/ I

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); $ c; T8 c4 N9 a# N% s程序例:

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#include ! E6 v- {% w. \: j+ ~7 }6 }4 f3 @#include % A" T. d9 e1 Z: ^6 ]) S3 L#include ( l8 H( N& z: z/ L9 p1 } H2 b U; n#include

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int main(void) { 5 G) r+ x& ~, I) k! g/* request auto detection */ ; `7 P1 u" w7 @+ w, @" f/ {int gdriver = DETECT, gmode, errorcode; + T! u& B7 l) z5 D1 u+ `: Kint midx, midy; int radius = 100;

/* initialize graphics and local variables */ - @/ b) I4 s5 o& Finitgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ 5 i- U8 q; O% [% ~, T% J+ X{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); ) }6 O; D- c+ r1 ]& Mprintf("Press any key to halt:"); $ d5 Q4 r# u% n; d* qgetch(); - t: Z0 S! d7 W4 b5 ~' P, N7 Zexit(1); /* terminate with an error code */ }

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

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/* draw the circle */ 1 t7 W; J3 k# o. t: k( \- o u6 Ecircle(midx, midy, radius);

/* clean up */ $ B0 P) A, y4 q; Sgetch(); % M6 U4 d) a( y2 wclosegraph(); h0 ? v* r3 D" Oreturn 0; } 9 ^ F9 N4 _3 _/ g `5 Y; R( C( x6 _! `) e # e! v2 }3 N. @5 ] z

函数名: cleardevice 功 能: 清除图形屏幕 用 法: void far cleardevice(void); 0 X% v3 B- N' i" h' F# J/ E1 t% A程序例:

#include / `& j4 M; ^! C- Z% H5 {; N" U#include & y8 J6 o% ~( X/ J$ O#include % \7 U. D, ]( }" p: E& y0 z5 t; T#include

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int main(void) { & e0 \" r, P V( l# L/ I( ?8 z/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy;

/* initialize graphics and local variables */ - t: d) x6 l# v; G, O5 einitgraph(&gdriver, &gmode, "");

/* read result of initialization */ 6 ~% m& s1 A- i" W& S# R8 S4 @errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ K. I+ R2 H8 L5 r{ + s) [, i5 m. ?* B6 g3 J) yprintf("Graphics error: %s\n", grapherrormsg(errorcode)); * t, T. D! J7 g# E! Gprintf("Press any key to halt:"); getch(); 9 R3 W: u( P2 }% `% u' \, K: @exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; midy = getmaxy() / 2; ) h# h0 S% o, W+ V, y7 e3 B& C# {setcolor(getmaxcolor());

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

/* 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 */ & U8 j6 N' W' D1 Ncleardevice();

/* output another message */ $ V' X, N% @' P6 R9 Douttextxy(midx, midy, "press any key to quit:");

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/* clean up */ . W: f! i0 D6 ygetch(); closegraph(); 4 H6 @0 j4 n/ C6 L; B9 ereturn 0; ( M( o( Z. v# |; n' _1 i} 0 p6 {7 z. d& g" r& M " x6 D$ S2 y$ _ " z8 U8 n% v* m9 |3 u8 V; C

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) { FILE *fp; char ch;

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

/* force an error condition by attempting to read */ - M: s# Q1 F3 h' ]) R; L* Gch = fgetc(fp); printf("%c\n",ch);

if (ferror(fp)) 5 x, z' v$ L1 \3 G{ " b: [/ I" V$ \1 \/* display an error message */ printf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ clearerr(fp); }

fclose(fp); return 0; } . Q" T, a+ W9 h

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函数名: clearviewport . ~6 r2 g) h0 Z2 N5 H功 能: 清除图形视区 / g7 q1 p" K/ e+ h+ ]5 g- T$ v用 法: void far clearviewport(void); 程序例:

#include & @/ `& k! h& }4 b; O$ ]#include #include #include

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

int main(void) . `" q2 q, m+ {{ /* request auto detection */ : c6 w* A* t4 eint gdriver = DETECT, gmode, errorcode; " ]" p" g1 u, W; K& k! A- }int ht;

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

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ) F* w: {7 M5 T! e{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); % S$ {3 M$ G, D h. l k- \ht = textheight("W");

/* message in default full-screen viewport */ " y/ |5 k) {/ p, K% [3 W3 \outtextxy(0, 0, "* <-- (0, 0) in default viewport");

/* create a smaller viewport */ 1 \" R8 J8 C. @9 n& Zsetviewport(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 */ clearviewport();

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

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/* clean up */ u8 ]" N, h9 T* V! G" A2 tgetch(); 7 D/ q6 ~! O, h4 O# Q! I3 hclosegraph(); % Z/ q' `4 ~; |3 v h: sreturn 0; } 1 ~6 `8 I6 k* o1 W$ B. g$ c% g

函数名: _close, close 2 L. o; @: O8 b3 k9 G/ l8 \功 能: 关闭文件句柄 用 法: int close(int handle); 程序例:

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#include #include #include ' c A7 |6 Z9 |* H#include

main() { 3 W4 v0 y$ Z! Vint handle; char buf[11] = "0123456789";

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/* create a file containing 10 bytes */ / z* f, a8 G, U- F8 p& e' k" Vhandle = open("NEW.FIL", O_CREAT); if (handle > -1) { write(handle, buf, strlen(buf));

/* close the file */ close(handle); } 9 g# |& h2 T: ^8 E- welse : {" G/ u7 u. y0 B0 j7 d) L{ ) P. K1 }* v& Oprintf("Error opening file\n"); } return 0; } 6 }7 V( ~# Z2 B/ t 7 h7 o! n( b$ x. r, B9 A ! h! p+ ~1 C4 U2 ? i8 Y" a3 s

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函数名: clock 9 F0 o7 u! `; x* U功 能: 确定处理器时间 用 法: clock_t clock(void); 3 Q2 Z: K" u8 \& n" X程序例:

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#include #include #include

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int main(void) { ! R: s! B% r0 cclock_t start, end; ( g' U) m3 E% wstart = clock();

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delay(2000);

end = clock(); ' i6 C0 \0 S( a( D" p% B2 Iprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; 0 y" g6 p; D* F) c} $ d0 ]6 y# J5 {) ?+ I7 m7 a/ }

函数名: closegraph 功 能: 关闭图形系统 用 法: void far closegraph(void); 程序例:

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#include #include #include #include

int main(void) ' J+ r( I% @, D% |" X9 g+ X; B{ 8 K, c4 g4 ^$ u& g+ y, Z4 P) l" C( S/* request auto detection */ 6 v/ U0 k& I8 C1 v* ?8 w/ cint gdriver = DETECT, gmode, errorcode; 3 l7 ]1 y4 y9 q+ h$ A' Q* {int x, y;

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

/* read result of initialization */ ' b% K o e% x; n4 I3 derrorcode = graphresult();

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if (errorcode != grOk) /* an error occurred */ . X# x/ U( c) `6 m{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 9 V4 i* w6 T! L! `}

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

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); ) N& ]3 ]: r9 e3 routtextxy(x, y, "Press a key to close the graphics system:");

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

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/* closes down the graphics system */ $ J& ^3 G* A" {closegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); return 0; } $ x1 O) C" H! H; `4 _. s b j/ G! g! q. h1 v7 t( X c) r

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函数名: clreol + H* r9 ]: B6 h: U' R# l功 能: 在文本窗口中清除字符到行末 ; m! V: t1 T6 w& e- T9 d) }用 法: void clreol(void); % i* @3 u! B4 _$ ~) u3 G _程序例:

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#include

int main(void)

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{ clrscr(); * }% R& Z6 M }: B; y) Lcprintf("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"); * m2 B, |$ B: ?* D+ }1 ]5 Pcprintf("Press any key to continue . . ."); gotoxy(14, 4); : x# [. F9 s6 s' U1 `. e. q' ^getch();

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clreol(); * U' ^& ~ }: P2 egetch();

return 0; ; r0 O" T- O: G) |, S+ c} 9 A* f" R* x3 p 0 M: M% r* V0 ~1 s! h H

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函数名: clrscr 2 _! z- b) \/ ^3 o& R( A功 能: 清除文本模式窗口 ; v0 X1 k2 g0 h6 _0 C. [- B用 法: void clrscr(void); 1 j6 O$ E- R; b) t1 i/ q Y+ h程序例:

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#include

int main(void) * ?- d3 D; e; d ^+ _# _/ o{ int i;

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clrscr(); , J. D! y# N( J3 k3 N3 @for (i = 0; i < 20; i++) & y4 ^& W, w2 X, ?3 h' ~: S% b" vcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

clrscr(); cprintf("The screen has been cleared!"); 0 a8 L% |, h) S, m8 {0 Y9 r9 W! wgetch();

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return 0; } , T' L) ]% x/ A4 M+ m9 `% O3 j7 H : c$ k& o$ ^2 M6 r4 N$ p" j. \$ [

函数名: coreleft % B% `6 k; C( w功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); ' v, u" w+ a8 I' _程序例:

#include & h0 {6 T. h5 j% G8 V( d- W! C#include

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int main(void) y. ^2 Z! f8 W& S* z{ 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; 0 k) }5 v1 k4 S$ u& u} 2 o5 |+ t* X* N. M+ l

函数名: cos 功 能: 余弦函数 9 ?, a9 w4 J" x8 m2 ]3 I4 U+ M用 法: double cos(double x); - Q% T9 y* U9 ]# x; ?+ v4 O! Z程序例:

#include #include

int main(void) 3 b! l$ t# @9 z4 P5 E+ v' y) X{ 4 O6 P6 u% p7 r6 D1 e1 X5 _) }3 p) kdouble result; double x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); return 0; } + S7 ?7 b, W& L! g2 N 1 U7 E3 h. M# a/ M3 a) i7 M

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函数名: cosh / j b9 d- S% A: c& h' z1 X功 能: 双曲余弦函数 ; P1 S. X# P+ l" m& S/ {; I/ d$ E用 法: dluble cosh(double x); # s5 U4 @) j9 i程序例:

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#include #include

int main(void) 7 M# d+ d8 Y3 g q1 x- x& E{ + X) M7 ?7 T% q0 C4 y0 k8 P) ]double result; 5 Q9 y+ u! u0 U+ I8 M- Mdouble x = 0.5;

result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); # j' z& _+ F* B3 y/ i4 ureturn 0; } , c5 N5 t5 N: ~ " P2 s' {7 A @) t0 w T

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函数名: country 功 能: 返回与国家有关的信息 , o" e4 s: M. Y' V/ x用 法: struct COUNTRY *country(int countrycode, struct country *country); 程序例:

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#include W+ t8 ?. q3 {) a& P& V6 f#include

#define USA 0

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int main(void) 9 Y1 `- ?, I5 q1 G9 A; x# S{ struct COUNTRY country_info;

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country(USA, &country_info); ( ~! Y6 ?4 k) m; K/ n3 wprintf("The currency symbol for the USA is: %s\n", / _3 ^6 D( T d; ?country_info.co_curr); 0 d8 N T+ z, U7 M5 h R( hreturn 0; " i& ]% H( b4 S& q3 h$ e& a, e} / H/ [% l% B0 k

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:

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#include

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int main(void) { T4 h, w C/ c/* clear the screen */ " a1 v0 o; P; H2 n8 Q" Kclrscr();

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

/* output some text in the window */ % |% _' b4 y9 W$ Z3 Ycprintf("Hello world\r\n");

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/* wait for a key */ 1 h0 [5 ~1 f2 k7 x5 _! O. \getch(); ( o* P6 r% f$ E6 L- ~! Q s3 |' ~: Dreturn 0; 8 N: L$ D, B% ]$ K ~} & W& q$ `5 a) s L1 w: ?* A

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函数名: cputs 0 ]3 W; v" D0 S- u: ?* K+ {6 \功 能: 写字符到屏幕 . T6 z1 B' |# K# H r1 D用 法: void cputs(const char *string); - M: g3 I# q& z _程序例:

#include

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int main(void) { /* clear the screen */ # W1 ^4 w9 v s2 f# n* v$ zclrscr();

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/* create a text window */ $ A, s9 f" j( S- c, L* Cwindow(10, 10, 80, 25);

/* output some text in the window */ 4 k% C' l/ @# bcputs("This is within the window\r\n");

/* wait for a key */ getch(); 5 U S+ N0 c4 X/ b, k" Ireturn 0; } 3 b& g( V- m, Y/ X- l" @ ( V6 f/ ]9 g- @5 Q$ k# C

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函数名: _creat creat 3 z% m; k3 s: \# s/ w c& J; k. E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 1 Y0 }- P( i0 _& y7 H4 |5 d1 f/ k#include 5 v. i9 T7 @: k2 D& u/ {9 u6 G8 C, n#include , g8 p7 g2 M' w% Q0 [+ b#include

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int main(void) " ?" }. t& R0 `3 Q5 J) @ p{ int handle; char buf[11] = "0123456789";

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

/* create a binary file for reading and writing */ 5 o' j2 X4 w% q/ k; G8 ~6 D5 jhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

/* write 10 bytes to the file */ write(handle, buf, strlen(buf));

/* close the file */ close(handle); . ]8 _( O. d$ o+ c7 J% Q( \: yreturn 0; , Y: ]: j+ n8 @ ]$ @8 I}

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函数名: creatnew 功 能: 创建一个新文件 : p! A" t5 c1 T3 [) Y) V: M用 法: int creatnew(const char *filename, int attrib); 2 @$ i9 d3 b4 S5 k程序例:

#include #include #include #include - W3 }" ^! Q0 ^8 @#include

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int main(void) { * Z6 ?0 b+ W9 V. V# H, ^int handle; char buf[11] = "0123456789";

/* attempt to create a file that doesn't already exist */ handle = creatnew("DUMMY.FIL", 0);

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if (handle == -1) printf("DUMMY.FIL already exists.\n"); ( c5 X2 A$ C: V8 Y, l# A3 relse * B6 I; C/ W$ ~. H{ 3 y7 S3 _5 Q7 \1 vprintf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); & `- f( }" ?, ~$ [0 Iclose(handle); + W# v+ T# x- z# o* O} 8 z, I! ]6 t/ J) o2 areturn 0; , p) t, y3 D9 P1 c. k$ H1 ]6 v} 9 U: l7 s' C' x1 m$ s; S3 Y% c " i/ U# u+ ]- r) u6 t) W3 O 9 j- G! n+ B8 i) r$ x9 O! b' R

函数名: creattemp 功 能: 创建一个新文件或重写一个已存在的文件 & m4 S2 ?2 B0 J) o% o" f用 法: int creattemp(const char *filename, int attrib); & h; Y$ B3 J+ Z' I2 ?程序例:

#include 2 [4 l& x/ a5 U% s- }% ]#include " `- [& v# _, Y; ]1 d. ]#include

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int main(void) 4 S5 R% K F) _5 _1 F, Y8 k{ 2 l. c8 {) V' a8 }/ e4 E8 p- jint handle; ( y( ^3 ~% D- kchar pathname[128];

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strcpy(pathname, "\\");

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/* create a unique file in the root directory */ , v& g) {: y/ I( s2 @3 Vhandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); close(handle); return 0; } : b. P" u2 b6 p

函数名: cscanf 功 能: 从控制台执行格式化输入 8 ?1 T7 \5 V7 s1 s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];

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/* clear the screen */ 1 T0 L6 f+ R. Pclrscr();

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/* Prompt the user for input */ cprintf("Enter a string with no spaces:");

/* read the input */ 8 |. y" a# q. Z2 Hcscanf("%s", string);

/* display what was read */ cprintf("\r\nThe string entered is: %s", string); return 0; 7 [" f( d$ {1 k) L2 [/ x} 9 L/ H- `( H7 r

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函数名: ctime ) j6 `8 @' v# x+ S' j功 能: 把日期和时间转换为字符串 用 法: char *ctime(const time_t *time); 程序例:

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#include 2 A: c& J9 o, g* ~- G. b, E( S#include

int main(void) { + i7 _! M: u; {1 Q6 \time_t t;

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time(&t); printf("Today's date and time: %s\n", ctime(&t)); @7 `* L; N3 M# R, d; Mreturn 0; * s$ @; S5 J% |4 F D} " R- m: X* V; `* H& u/ j. Q

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函数名: ctrlbrk 2 E& N9 I. S4 T1 y/ M$ x1 M功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 程序例:

#include ! [8 Q/ j3 b" n4 `- n; M. j# W#include

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#define ABORT 0

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int c_break(void) 1 f/ `! M" \8 Y4 s# T, i0 [{ printf("Control-Break pressed. Program aborting ...\n"); / r7 ^* h! m% R' s8 {$ P% Ereturn (ABORT); . L& D: m# p; K {( R% [}

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int main(void) 2 |7 Y9 [/ h. u. j0 _3 A" s' P& a{ ctrlbrk(c_break); # b- J7 }# s3 T5 ]6 qfor(;;) 4 d8 U5 V, I* h7 x9 H, M7 N{ , H9 l6 t# b2 l# z! d% r7 Rprintf("Looping... Press to quit:\n"); ' h' S; ]- {& T6 y. g} 3 D# G& ~- r, B8 i) e7 `& Sreturn 0; }

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