函数大全(c开头)

韩冰

函数大全(c开头)

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函数名: cabs 1 h0 C! ]+ f+ K5 ^; D6 k+ t功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 程序例:

#include #include

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int main(void) ) ^; k* h' f. Y1 H" t6 D8 M: J: q{ 8 T5 G+ j. a# A7 L4 }2 ?9 }0 w' lstruct complex z; ! O E$ T: c" Z0 N- } P4 Bdouble val;

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z.x = 2.0; : i4 D3 a) n9 I O9 j/ M) p1 Iz.y = 1.0; val = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); , p6 B1 H3 Z7 \return 0; } ' _0 N# V$ `3 b% C1 y

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函数名: calloc : h, v' v4 s6 `功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); 0 F/ y; L) q3 X程序例:

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#include ; H; K# T( I" t$ U0 O: k#include

int main(void) 0 ^2 K( f: v* g! @. s$ M/ M{ char *str = NULL;

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

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/* copy "Hello" into string */ ; G/ R5 ^" ~6 n9 {strcpy(str, "Hello");

/* display string */ 8 A) K+ w) \+ E( kprintf("String is %s\n", str);

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/* free memory */ free(str);

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return 0; , i/ v: P+ v( d/ u1 p4 T} ! i6 S7 [) P0 ^2 `/ M% T $ D/ y! Y, R6 B9 q1 [! Y

函数名: ceil 4 K( _$ \$ F, m& _. v7 F. M功 能: 向上舍入 + r3 q: d$ P8 L; ^) t; A用 法: double ceil(double x); 程序例:

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#include $ E" i& C: B! j8 x, b6 O9 K- w4 p#include

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int main(void) { double number = 123.54; double down, up;

down = floor(number); 8 U% I1 N' X0 B4 cup = ceil(number);

printf("original number %5.2lf\n", number); / p B2 y) @% N3 Uprintf("number rounded down %5.2lf\n", down); printf("number rounded up %5.2lf\n", up);

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return 0; } 4 U" S/ x1 Z* ]4 {

函数名: cgets 功 能: 从控制台读字符串 9 T: H0 ~! O' n. ? a用 法: char *cgets(char *str); 程序例:

#include # w* b. L6 }( Y#include

int main(void) 6 z/ ?& C* w7 i' w{ 9 E3 T1 O3 Y$ m+ {& ichar buffer[83]; char *p;

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

printf("Input some chars:"); 9 ]5 U* W/ ?/ @- j" ^p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 3 L% V9 c- U, g% j: K5 Q, Aprintf("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:"); 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); return 0; ( p4 R. B3 ^9 \- t4 T} ( }' ?0 ~- y2 t# B% H3 I3 \# w : E/ m" X$ O* b+ T

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函数名: chdir 功 能: 改变工作目录 用 法: int chdir(const char *path); 程序例:

#include W& k$ x W3 e#include ! y% [7 g4 R4 @# w3 z#include

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

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int main(void) " i3 |5 M; G) V; i1 `: u{ 6 i. ]( x( x' j* Hif (getcurdir(0, old_dir)) { . P$ `6 b: Y; R7 Pperror("getcurdir()"); exit(1); } 4 D& B, s& O2 ]: O3 _printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) % |/ K- f" _. ?{ ! z- |/ f. h9 x1 `0 F4 iperror("chdir()"); exit(1); }

if (getcurdir(0, new_dir)) { : N7 `& w7 W9 U& _# i5 vperror("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)) % s# t* x! F8 z4 k{ 9 B* `5 q9 M) u( iperror("chdir()"); exit(1); }

return 0; 5 b/ `9 m# ~- w4 W1 g} / P2 t$ O! w! |3 p 9 I+ }2 c) F- V/ r

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函数名: _chmod, chmod 功 能: 改变文件的访问方式 ; `, u2 D9 u9 ^用 法: int chmod(const char *filename, int permiss); 8 X* h2 U# m) u1 X" K程序例:

#include . y S) h |8 ?) I7 I# ?8 d- v#include #include

void make_read_only(char *filename);

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int main(void) { 8 p! o& S3 C1 f& g! ]& O4 P; Qmake_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); return 0; }

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void make_read_only(char *filename) % \8 m4 z1 n3 d' Y: Y) | V+ [{ int stat;

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stat = chmod(filename, S_IREAD); 1 q K/ A3 P& Yif (stat) printf("Couldn't make %s read-only\n", filename); 7 j( m, h6 d$ D, h8 ?" oelse 2 h. @1 J* k1 I! tprintf("Made %s read-only\n", filename); ( H: S1 g1 L( F: d; w3 A0 L- P" c2 o} 2 R: g, X0 z1 k % D) I- a# I9 p' O( Q

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函数名: chsize 功 能: 改变文件大小 1 Y V; F* Z) Y; n0 f用 法: int chsize(int handle, long size); 程序例:

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#include #include . c" p* X2 _# u. j1 n. E#include

int main(void) { int handle; 7 ]1 R5 _9 F( J5 |: b1 Hchar buf[11] = "0123456789";

/* create text file containing 10 bytes */ - S: Q7 ]) J7 `) F, i1 s: h# Vhandle = open("DUMMY.FIL", O_CREAT); ) l8 Y5 P% f* R" G7 @write(handle, buf, strlen(buf));

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

/* close the file */ % f7 G, Y4 ^/ x0 N Zclose(handle); - c7 h& M3 X0 d9 m4 x/ v7 v3 n1 xreturn 0; }

函数名: circle % Z$ B9 a# \4 o- Y/ a7 I7 _7 E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); 程序例:

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#include #include #include $ b) Q; } B6 h# p#include

int main(void) { 3 a& E3 P) A5 A: h/* request auto detection */ 9 ?! K2 R+ `$ ]; }: p) k! |% M6 Fint gdriver = DETECT, gmode, errorcode; 8 g% S( p0 P# ]' Tint midx, midy; ' p+ l% ~- l: ?0 Oint radius = 100;

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

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ M& y, I- D+ L* x7 _% K{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 J# k* Q2 Q) h2 t7 u7 G( p2 Z2 jprintf("Press any key to halt:"); : g3 _* Q+ D ^$ n& c: U/ q- Bgetch(); * g4 r# d6 w }* T8 e5 fexit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; + b4 R) |, h+ K! ?midy = getmaxy() / 2; 5 }( ?% ^) B& H! ~setcolor(getmaxcolor());

/* draw the circle */ - N2 @4 H7 c5 p' Rcircle(midx, midy, radius);

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/* clean up */ $ A& {6 ^7 S! rgetch(); ' U% r7 j! E; K' F, G! o5 C& Yclosegraph(); return 0; } ) a+ E1 U: A1 o) {/ c8 E5 k * c O$ e+ U% }" J" V! M% r! a4 G( f% V

函数名: cleardevice $ \5 H8 N# W3 ^$ M1 ~9 m5 f6 ]7 A功 能: 清除图形屏幕 1 h' v. r" \% u- D用 法: void far cleardevice(void); 3 J. I1 |6 H |1 ~: _程序例:

#include #include #include * m2 ~$ R3 E0 r" S( b+ M& K5 [7 o- G#include

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int main(void) { 1 a+ `, J: x+ k1 P! K' K* T) @/* request auto detection */ 6 |, o8 l5 ~4 vint gdriver = DETECT, gmode, errorcode; , G! r9 G* i: [/ X5 i9 {int midx, midy;

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

/* read result of initialization */ 3 H# A& G' U! berrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); ' o9 _9 i* o$ \; Q" z! Bprintf("Press any key to halt:"); 3 J3 x0 W) r0 |$ lgetch(); exit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; $ y0 R7 M7 H0 W8 O$ Zmidy = getmaxy() / 2; setcolor(getmaxcolor());

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

/* output a message to the screen */ ) c: H. L( Z9 o' a: nouttextxy(midx, midy, "press any key to clear the screen:");

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

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/* clear the screen */ cleardevice();

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

/* clean up */ 5 h/ ]5 F1 r! G/ qgetch(); closegraph(); return 0; } 7 B8 v% b( W- A/ q1 g3 g + Z6 p9 U6 E" k! V9 p" ` $ r. D+ s' z8 b1 v

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

int main(void) { 3 q8 [1 s% g, ^- rFILE *fp; , ?0 N7 ~5 }5 f! Vchar ch;

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/* open a file for writing */ ! X7 c9 c3 e3 J. l" o! }fp = fopen("DUMMY.FIL", "w");

/* force an error condition by attempting to read */ ch = fgetc(fp); 0 _4 y" V! u, b* L% ~printf("%c\n",ch);

if (ferror(fp)) { /* display an error message */ printf("Error reading from DUMMY.FIL\n");

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

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fclose(fp); ( A* q9 L4 Z. [* y) Zreturn 0; } $ a- g( V" T9 U2 w/ f' C

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函数名: clearviewport 功 能: 清除图形视区 用 法: void far clearviewport(void); 2 H; {' ^- @9 F2 k% y$ q6 H程序例:

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#include #include #include 2 U( j1 P$ ^9 `5 r1 M#include

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

int main(void) { 2 E( X, [$ K' w* L% c8 Z- H/ U! c2 A3 p/* request auto detection */ int gdriver = DETECT, gmode, errorcode; + I- K6 }* E$ P2 |0 D$ yint ht;

/* initialize graphics and local variables */ # e Z$ {' X% sinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult(); {( s, k2 l3 M' b1 lif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); , U) Z) F" M% ^. R6 Qprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); $ R; y3 `" b7 D( } xht = textheight("W");

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/* message in default full-screen viewport */ / X# c* d# a2 s2 A# t/ Qouttextxy(0, 0, "* <-- (0, 0) in default viewport");

/* 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"); . ]0 V( X0 ]0 U% A8 h' k7 l" uouttextxy(0, 2*ht, "Press any key to clear viewport:");

/* wait for a key */ 6 _( f( k, T% Jgetch();

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/* clear the viewport */ clearviewport();

/* output another message */ + W) h* J* T* C9 k0 houttextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); ( S( K( A1 v, `* W2 `closegraph(); return 0; } 0 T# Y) w5 J* E" k g5 ?# \ " `+ O0 j! c8 f6 r/ B

函数名: _close, close 功 能: 关闭文件句柄 : F) k2 C) H$ X j B5 X/ [用 法: int close(int handle); 程序例:

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#include #include #include #include

main() , C. B# V& h! l3 d3 K J& _+ j{ ) l6 C) q8 X! N- f2 b' X: s$ G+ Yint handle; 5 p. f9 c: a3 A q* D8 w( t! ychar buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); % q' q" k8 T, aif (handle > -1) { 0 q. ^9 g/ h$ u2 xwrite(handle, buf, strlen(buf));

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/* close the file */ close(handle); 8 K' b+ ]7 u& H} else ( `5 e) m: U( R+ J0 \' }{ . I+ F0 U! Z8 E, _: x# C- R+ E9 wprintf("Error opening file\n"); 6 y* |& a9 Q8 Z! w& \2 I/ @/ w3 a} / P8 B% m" g' G4 treturn 0; } 0 C' m# v$ O3 w/ {: Q- W0 v& r

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函数名: clock * ]( \# |8 p0 Z功 能: 确定处理器时间 用 法: clock_t clock(void); 程序例:

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#include / l$ I3 Y3 y4 |$ a1 p( R#include 5 j: P) S" R# I0 E2 C) z#include

int main(void) { clock_t start, end; start = clock();

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delay(2000);

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

return 0; }

函数名: closegraph + ~; v6 V3 p6 c; ]! w* Y! Y功 能: 关闭图形系统 & l) N3 ]8 [5 l$ c用 法: void far closegraph(void); 程序例:

#include + w% N( P& p; M* d#include & Z2 Q8 s" M% ]) V6 i; e#include #include

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int main(void) { /* 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 */ errorcode = graphresult();

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if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); ' {0 L# }6 Y2 ]2 a) z( nprintf("Press any key to halt:"); ) i5 u. T. y6 g! `- p# Ggetch(); - Y' C! N: ?6 `exit(1); /* terminate with an error code */ }

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x = getmaxx() / 2; 9 V3 L: I' P* O7 x: Ty = getmaxy() / 2;

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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/* wait for a key */ 4 w* T1 L/ f0 a' f2 i( \% w3 ~- B1 Sgetch();

/* closes down the graphics system */ & W2 l! j8 Y. G/ }9 S( B0 mclosegraph();

printf("We're now back in text mode.\n"); 4 ^4 G) U. F3 Y+ Q0 Nprintf("Press any key to halt:"); 1 S& f" G/ b* U* s; jgetch(); 2 N9 J7 h4 T9 v& @- O* N- |return 0; }

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函数名: clreol 功 能: 在文本窗口中清除字符到行末 * g( o8 b) [1 D! I' k用 法: void clreol(void); 程序例:

#include

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int main(void)

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{ $ Q" ]' i% {# t& h, Q+ H" Oclrscr(); cprintf("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"); 5 a2 V- ~& p# I3 E/ B$ ^ Y% Acprintf("Press any key to continue . . ."); / N1 _1 H7 e7 g1 D: Kgotoxy(14, 4); getch();

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clreol(); . J; h; H. P+ s7 P7 mgetch();

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return 0; ( x3 r$ k1 ]# Q# M} ! Y u; H& `1 m" V

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函数名: clrscr ; L: U& g% D6 ~+ I( ?0 I% H功 能: 清除文本模式窗口 用 法: void clrscr(void); , a I) ]# q/ |7 L4 M程序例:

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#include

int main(void) " e* O$ @3 ? ?{ & T) ~- ]; I- Y6 Dint i;

clrscr(); 3 P0 _5 t$ l# {3 }/ E. ffor (i = 0; i < 20; i++) ! H9 _" @% o3 f! P& r+ kcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); x- n, w6 U; tgetch();

clrscr(); 4 z4 C5 A$ c9 m* Zcprintf("The screen has been cleared!"); 4 Q$ [5 M" o9 Mgetch();

return 0; } 7 s. q* q. O7 c3 J. J% \% k# a% [# x - w5 w1 V. }" F2 r : v8 B, S" \% j0 k5 ]

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函数名: coreleft ! k+ Z3 F3 k: t" n/ d, w2 e" U功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); 程序例:

#include ! A% h1 y" \6 j' ^#include

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int main(void) { 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; ) `4 @$ F D7 X, b S1 ]% C& p} : D- n# l8 [5 N% d6 l

函数名: cos 功 能: 余弦函数 用 法: double cos(double x); 程序例:

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#include #include

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int main(void) { 5 A$ X+ p0 \ l# g u; C+ [6 cdouble result; double x = 0.5;

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result = cos(x); 1 L/ B! ^6 w: ^# W% \, P* `printf("The cosine of %lf is %lf\n", x, result); # [+ T8 X3 u1 k, u" k$ C1 Mreturn 0; 2 h8 C9 o g6 L" r t k) g} 2 l8 O8 K) ?; E" S0 _- K * S; `: E& ^2 G" b1 B' l/ ~

函数名: cosh ) r* Y) f' \8 g$ g7 Q; e3 d# r# G功 能: 双曲余弦函数 用 法: dluble cosh(double x); 程序例:

#include & U, c9 `$ o5 i+ l1 j& h, X#include

int main(void) { " n- z$ c0 O0 q. e0 N' Q0 L* p" }double result; 6 E) G# N5 k* Q3 r; ]( M& ddouble x = 0.5;

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result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; 4 R% w5 R6 r! z} ' P4 Q( o& b! ~! S J: ~ * P" E+ t" A+ X( ?, R4 `

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函数名: country 功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); 3 M' u7 j9 m; x4 ^7 g7 J程序例:

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#include #include

#define USA 0

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int main(void) ! |7 Q/ I# i _3 q! _. y7 D{ struct COUNTRY country_info;

country(USA, &country_info); $ S) f( Z! v$ i6 D+ aprintf("The currency symbol for the USA is: %s\n", country_info.co_curr); 6 V7 H6 F2 f$ l2 [; A( ^( mreturn 0; } 0 W4 X: `! y6 ~/ c# @ + m6 W$ ?! f t) p( ^/ f" M

函数名: cprintf / |, U, h) C$ G2 l$ c0 t2 \功 能: 送格式化输出至屏幕 : ?+ l/ z+ f# d# z6 _! R; r用 法: int cprintf(const char *format[, argument, ...]); 程序例:

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#include

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int main(void) { /* clear the screen */ ; }6 b2 e0 y' F% R8 j( O' dclrscr();

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

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

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/* wait for a key */ . d, H4 a! v- m% K$ j, [7 o: lgetch(); ' z7 u6 O9 M. z% y5 a) jreturn 0; ; N1 S( ~0 z# D1 U, y4 a6 h} ! S. ~* y# o& @; A + v( d% M3 H: r# t: v- D! S ! M6 m' P- K6 V( X6 s

函数名: cputs 功 能: 写字符到屏幕 3 }4 l {/ |' X: T3 p, D4 H' ?" w, ]用 法: void cputs(const char *string); 程序例:

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#include

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int main(void) { /* clear the screen */ clrscr();

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

/* output some text in the window */ , F. k! a+ |. w/ s" Zcputs("This is within the window\r\n");

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/* wait for a key */ , C$ R3 @/ ]4 a0 B+ N; k lgetch(); , A7 a7 [+ E* [) P3 r/ l& b$ g/ e) oreturn 0; } 4 a, @7 T- M* A$ A. ] 1 t7 d7 |) f2 D* b" F2 x' d

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 . S" z) _+ v3 z6 R用 法: int creat (const char *filename, int permiss); ; K0 s; a- f$ S" q4 X程序例:

#include ! {8 \1 m! ^+ ]: f#include , C: Y* E- v% Z( x. X#include 3 j! y, |! O8 f; P. o#include

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int main(void) " \# l* Y* A( k1 V$ z{ / z$ {3 P Q: Y s) }+ y0 Tint handle; " S' K/ L0 y; @. Rchar buf[11] = "0123456789";

/* change the default file mode from text to binary */ 7 B, _( v5 _- ]+ }$ f5 h$ i_fmode = O_BINARY;

/* create a binary file for reading and writing */ handle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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

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/* close the file */ close(handle); n" z w8 h6 e" r0 }! sreturn 0; . w& r# E& |0 }. ^* l8 X} - o7 J1 L2 y i& k% K. T/ X

函数名: creatnew ) V* ]; `" A7 F3 ~# q功 能: 创建一个新文件 用 法: int creatnew(const char *filename, int attrib); 程序例:

#include 0 [9 f% W1 h% p# G; j! J0 ]* J#include & L1 `' }+ Z3 ~7 k#include #include #include

int main(void) 3 f% D. Z5 Y5 R8 E1 S) A7 B8 x0 g{ int handle; 3 d6 y& Y( C- Y( l8 \1 lchar buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ 0 S. X: B4 x; w8 Z9 hhandle = creatnew("DUMMY.FIL", 0);

if (handle == -1) - ?+ ^6 G0 h, y* @printf("DUMMY.FIL already exists.\n"); else 7 |1 D7 d2 w5 E{ printf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); 0 L' d" U$ m; |: L1 bclose(handle); 3 x/ `& F3 x; o. E9 k} ' V: ]( Y- {$ p; D3 o+ C7 |return 0; } , H5 B& s* |. u; D4 E) g

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函数名: creattemp 功 能: 创建一个新文件或重写一个已存在的文件 3 W1 {* P: t ]5 B: D用 法: int creattemp(const char *filename, int attrib); 程序例:

#include ( k0 d/ J6 u0 h$ `9 ?$ O8 ]#include #include

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int main(void) - l. J7 a0 H/ L* Y) L) f' V{ int handle; char pathname[128];

strcpy(pathname, "\\");

/* create a unique file in the root directory */ 1 G( J ]# ~* Nhandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); : a' {6 t2 p% ]close(handle); 1 r5 p1 E- X( ~* B- M- A% Q- I: o8 B4 areturn 0; * Y+ b5 U# F$ ^( |} ) N( o1 k- C) l6 K! T, _2 I

函数名: cscanf 1 S; g- }: R) E* j0 A6 l( j功 能: 从控制台执行格式化输入 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 */ clrscr();

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

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/* read the input */ 2 z) e4 q: X4 S8 [* Z- Acscanf("%s", string);

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/* display what was read */ cprintf("\r\nThe string entered is: %s", string); , K( [. c4 X% i( l* W6 creturn 0; ) L" f! m: F( I4 y% w2 f5 Z} ; J3 p5 x! k2 B* N' m* c8 d6 w6 j

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函数名: ctime 功 能: 把日期和时间转换为字符串 # H& ]5 A/ A4 {. _. }用 法: char *ctime(const time_t *time); & D5 j5 E4 m4 I) W8 p1 |7 J程序例:

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#include 5 J6 {" v3 R$ K; B#include

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int main(void) { , B( v( \6 c" G! O a# ftime_t t;

time(&t); 9 j! d9 H9 u6 y% |printf("Today's date and time: %s\n", ctime(&t)); return 0; 4 M) k; K$ _: g* v. f6 o} 0 J; N) s3 ]( u: v, O* L7 b4 `

函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 7 s$ \- V7 g- M4 i. f用 法: void ctrlbrk(*fptr)(void); 程序例:

#include #include

#define ABORT 0

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int c_break(void) 8 i4 j9 E d. N4 ~{ printf("Control-Break pressed. Program aborting ...\n"); return (ABORT); % u7 |: F. V/ W# ?- {}

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int main(void) " [7 Y$ M: ?4 S! ^- l{ ctrlbrk(c_break); / f' \. q( \% [6 a, i; j* Y2 wfor(;;) $ q i' c8 G2 k- G( T3 a' w5 P3 g{ printf("Looping... Press to quit:\n"); } ' _, f/ x( U' C: n- ^return 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