函数大全(c开头)

韩冰

函数大全(c开头) 9 q% K% Y) ^* p1 ~5 T% c1 ?

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函数名: cabs ( y& m. t- C( c0 Z8 [2 i' z: U; o; x功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); : m; Y( [7 P6 W& \程序例:

#include ; P1 Q5 Z9 b* q2 r#include

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int main(void) { struct complex z; double val;

z.x = 2.0; % `+ Z, k- L! T) O1 w7 nz.y = 1.0; : x/ O3 y& ]. q0 dval = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; } : a$ A& }2 R: f( \' I0 f

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函数名: calloc 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 " w# @: m1 E# p8 @' T, F#include

int main(void) : @! R% w; z: P# S- X+ o6 d* l8 G{ char *str = NULL;

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

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

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

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/* free memory */ 7 V/ q) r- ?7 Dfree(str);

return 0; }

函数名: ceil 功 能: 向上舍入 " [3 {1 `6 \. E( V用 法: double ceil(double x); 程序例:

#include " ]3 x! G% O/ D! s#include

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int main(void) { 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);

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return 0; & ^8 K$ ]; f, q} + C& n4 x. q; s* }( C 2 |* `6 h. i8 Y* E6 q$ R

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函数名: cgets 2 i$ ]1 x" r/ k功 能: 从控制台读字符串 + ~& a) ?3 Y; G7 Y9 @7 j用 法: char *cgets(char *str); + v: q# V9 ~- l3 B9 P/ ~! X% R程序例:

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#include #include

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

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

printf("Input some chars:"); p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); + m6 J' {+ E0 Vprintf("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 */ buffer[0] = 6;

printf("Input some chars:"); [6 Z; }5 m6 u9 E5 ^" o: r4 r! r' Q% kp = 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; } " G5 x1 J. Q9 w/ T- G3 X: @ 1 M; w) o/ G8 T& D' ~& d

函数名: chdir 0 l- p% ?* {0 |0 I9 A3 e! y( Q功 能: 改变工作目录 用 法: int chdir(const char *path); 1 |! I3 p5 c5 R: v程序例:

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#include #include 5 r; h& H# ~7 B4 O. J3 Y! W* [#include

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char old_dir[MAXDIR]; * v! B6 N& v. o3 D5 ]char new_dir[MAXDIR];

int main(void) % |: g& f. u1 V4 Z' c, e{ if (getcurdir(0, old_dir)) { ; o# [- C# l) g5 ]6 Qperror("getcurdir()"); " ?# j D+ o; F$ w2 k6 lexit(1); " }( a: y1 c7 q2 r) J3 e W% H/ q} printf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) * c8 y; E6 g* S5 j* P9 L{ 1 _3 X7 O- { Vperror("chdir()"); & a5 Z4 P' m/ Nexit(1); - D+ Q( G) e o' Z9 ]8 g0 n& C}

if (getcurdir(0, new_dir)) : V7 J! Y. {) ^% `7 m8 H1 z{ , Z* N6 V+ F5 \0 o# {perror("getcurdir()"); 0 `3 V2 s# y7 x6 ?exit(1); y2 C- `$ G$ K% P4 ]' }( d: B} 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)) * R: _7 ? T7 u" @7 E' [4 C{ perror("chdir()"); 3 X$ Y" l" ? y6 @9 y' sexit(1); . A. d3 p5 B. q9 c}

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return 0; } 9 s( o1 O; n) Z9 L$ H

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

#include , M$ ?3 [: c5 X3 ]#include #include

void make_read_only(char *filename);

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int main(void) B% N5 i- x, L- J{ * c" J0 _/ ^0 Lmake_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); 7 K$ v; |4 @7 d4 ureturn 0; }

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void make_read_only(char *filename) 8 N( q" X3 a& g; w& L. W M5 U{ : W2 _. c: l _# Q5 ^, ?int stat;

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stat = chmod(filename, S_IREAD); if (stat) 3 U3 M5 C$ t" nprintf("Couldn't make %s read-only\n", filename); else # m$ j" n, a' Y% y3 c% }' Dprintf("Made %s read-only\n", filename); 8 i, t# \( B6 i, ^& c/ {- \& T S} - h" z4 d- X- ^/ B$ u & ~/ A! x9 i7 @8 l9 m

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函数名: chsize * v, H: z; b7 A2 @功 能: 改变文件大小 用 法: int chsize(int handle, long size); : V8 |5 X6 g+ s: L/ j4 b, F程序例:

#include #include - G! N: q' Z- q, @, y" P+ B7 x#include

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int main(void) $ R+ ]) _5 I9 k: d3 K3 H8 v9 D{ int handle; 7 s6 H1 D/ w3 b/ s- cchar buf[11] = "0123456789";

/* create text file containing 10 bytes */ handle = open("DUMMY.FIL", O_CREAT); $ k6 p h9 T9 |/ a' bwrite(handle, buf, strlen(buf));

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

/* close the file */ # S' t. Z4 M( v& Sclose(handle); return 0; } 0 U# {( d0 J, Z" _& K- l1 T9 }

函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 % s; k/ t b; e' ?+ X; V9 X用 法: void far circle(int x, int y, int radius); 程序例:

#include #include . A; t$ F9 q* J- Q' I5 O+ C#include #include

int main(void) { . L: w6 m, k( V% t& g& T( T/* request auto detection */ + j8 c! ]8 n8 ?! a# j/ c1 vint gdriver = DETECT, gmode, errorcode; & _; Y( k& j I1 ^# l m4 T* o6 Y4 Iint midx, midy; int radius = 100;

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

/* read result of initialization */ 1 m0 G" L1 `' p' K6 ~errorcode = graphresult(); ' X# {0 W5 {% G8 B: e: E9 h8 @if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); * D' J" M/ H2 I" Tprintf("Press any key to halt:"); 8 R& m# y7 b% L7 [" @# V ^getch(); exit(1); /* terminate with an error code */ * K/ l" K' ]! i6 G}

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midx = getmaxx() / 2; 7 u" {# Z3 Y6 v, d% [midy = getmaxy() / 2; ! {8 `, C& F* P* F7 U% v1 U; ?setcolor(getmaxcolor());

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/* draw the circle */ . c. u& i- s" Q* hcircle(midx, midy, radius);

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/* clean up */ ) K9 _* Y7 g% q8 z+ Mgetch(); closegraph(); return 0; } 8 R5 |$ p3 b* D " G8 g, }5 U \+ S' V

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函数名: cleardevice 功 能: 清除图形屏幕 用 法: void far cleardevice(void); " @" x B" C$ j程序例:

#include #include - d# V( l$ B7 {#include , P/ i1 h# t4 a0 t; {#include

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int main(void) { ' m B& o0 r% K2 [' i6 K# g* Y7 ^/* request auto detection */ 2 |0 k2 E3 r# r- m& }! A/ Kint gdriver = DETECT, gmode, errorcode; int midx, midy;

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

/* read result of initialization */ errorcode = graphresult(); , }$ L) c. r0 x7 L _if (errorcode != grOk) /* an error occurred */ $ a: {7 j8 G2 l: b{ 3 w% X1 A5 [ e0 N8 Y) t% ?" w% [8 Rprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 0 D- x' |6 x; `/ x0 \# p0 igetch(); exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; midy = getmaxy() / 2; 9 [) _' H% F! y# s$ ]) _( `# Jsetcolor(getmaxcolor());

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/* for centering screen messages */ 5 b: w+ y' g9 l6 [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();

/* clear the screen */ . n4 x l6 p* c7 h) R Ycleardevice();

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/* output another message */ : F7 j+ N$ j0 Routtextxy(midx, midy, "press any key to quit:");

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/* clean up */ getch(); closegraph(); return 0; } 6 ]3 V% f/ [# T* {9 @$ r

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函数名: clearerr 功 能: 复位错误标志 ! o* C! X; Z' _; b用 法:void clearerr(FILE *stream); ; W0 v" t' ?2 Z; C程序例:

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#include

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int main(void) + b+ _ T0 v' k5 O# w' e{ FILE *fp; ( q1 l- p/ z5 ?# I6 ?char ch;

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

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/* force an error condition by attempting to read */ ch = fgetc(fp); / M& v& V) L' f0 n# z' S2 aprintf("%c\n",ch);

if (ferror(fp)) & e' Y* Y' ~8 W, E{ /* display an error message */ printf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ 7 B$ E7 A9 m5 i: J( U1 c6 o3 rclearerr(fp); }

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fclose(fp); . K$ n0 {3 A8 W; b" R; q! D% U0 Hreturn 0; * A1 T3 U5 D% P; d, ]} # [0 ~9 d2 j/ M! D+ I# H

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函数名: clearviewport 功 能: 清除图形视区 ! I* o' G6 P% t+ o9 G用 法: void far clearviewport(void); & |) O2 A+ |$ U# X5 i程序例:

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#include #include #include ) }/ B% Z M2 _+ q. G! s#include

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

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int main(void) { % J+ |: B3 O* B: |) @. N6 y" m% R( J/* request auto detection */ ( A. J# V9 ?8 eint gdriver = DETECT, gmode, errorcode; int ht;

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/* initialize graphics and local variables */ $ n# R. H |' l. x) Cinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ 4 z1 A {2 H# u" ]: berrorcode = graphresult(); : i6 j$ ^( H5 ^2 j& ]* Rif (errorcode != grOk) /* an error occurred */ 7 c1 @/ M6 x2 }% R6 Y" O* \{ & x% ?6 ]0 ?8 v1 u% Z, ^printf("Graphics error: %s\n", grapherrormsg(errorcode)); ' v0 r0 P. L' D y) T) ~printf("Press any key to halt:"); getch(); ( `+ K6 d3 M; J4 {0 w- iexit(1); /* terminate with an error code */ }

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

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

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/* create a smaller viewport */ * Z) x9 T; q# U3 Y! y+ u- Ksetviewport(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();

/* clear the viewport */ ! E1 e3 R8 }, Jclearviewport();

/* output another message */ : F' t& ?2 }. |, X( louttextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); 2 A- @ u% _5 |4 Z" {0 Q) ?closegraph(); 2 G+ _& m7 D7 wreturn 0; 3 w! Y! G9 ^, T1 w [0 W2 A. z2 B} , o6 @( @, y1 f9 A* Q8 g, i$ M* a ; o! ^! W3 g) Q2 w1 H 5 k; v% o0 u/ O1 d

函数名: _close, close 功 能: 关闭文件句柄 3 t" Z! _0 h5 P1 u0 b2 y用 法: int close(int handle); : f; g# u. d0 K3 K1 G7 ^程序例:

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#include & y6 T# G# S- M2 L8 ?#include # [7 u( K& a3 n: e. V h+ p#include #include

main() # |8 _# Z3 @5 f: I{ 4 a1 _* r0 C- Z9 Vint handle; 3 b. z) [' Y% Q m3 u6 h xchar buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); ; l. R+ b, ]7 _7 V: }if (handle > -1) 3 r" n" `+ C5 h- t( w& E9 I{ # ~4 t2 S, }. j" ^6 f* ^write(handle, buf, strlen(buf));

/* close the file */ close(handle); ' x) L3 t7 a$ q} . e) P# H( r5 melse 2 ^1 l6 R: b0 C' V4 t0 W3 r' j{ printf("Error opening file\n"); . ]: T8 q" ?7 i} return 0; }

函数名: clock 功 能: 确定处理器时间 用 法: clock_t clock(void); 程序例:

#include #include #include

int main(void) { 3 N2 u) D. ^8 B4 }$ _clock_t start, end; start = clock();

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delay(2000);

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end = clock(); 3 g4 ]* B& m7 B- _+ Qprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; } ) N+ z7 s! E8 m1 a/ _* s' W* M : m) a5 S8 O S

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函数名: closegraph 4 J, K% m. S( v. i: _0 f& y% h" k功 能: 关闭图形系统 3 D* H( H4 i# G! n% ^, H/ c用 法: void far closegraph(void); 2 Q O5 d" k( S程序例:

#include #include #include #include

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int main(void) { , E4 H5 V/ ]* n7 G+ J; o- b1 f/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int x, y;

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/* initialize graphics mode */ 4 t8 Y- |, M Y' S" B" ainitgraph(&gdriver, &gmode, "");

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

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if (errorcode != grOk) /* an error occurred */ + S* G0 J" K! N: x/ J, w{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 j, u ~3 J* X. Pprintf("Press any key to halt:"); " `, z$ F4 n2 z! Dgetch(); exit(1); /* terminate with an error code */ }

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

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/* output a message */ $ ]% K1 `/ R- d0 }* ?5 `2 I; Lsettextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(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 */ 1 |* w9 Z, U; Q" z- D" Fclosegraph();

printf("We're now back in text mode.\n"); 1 L, H6 @1 F( g+ lprintf("Press any key to halt:"); $ k1 C4 W1 C9 ^& M5 bgetch(); return 0; . X! e0 ^# J, V7 U}

函数名: clreol ' H$ p" e" C. b1 O$ `功 能: 在文本窗口中清除字符到行末 ) Y5 D) ?6 P( K! X) ^7 X! D0 C; Q6 s* ?) M7 r用 法: void clreol(void); 程序例:

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#include

int main(void)

{ clrscr(); : a5 E4 Y9 O3 i: ?+ s) n/ d% _5 g0 vcprintf("The function CLREOL clears all characters from the\r\n"); 1 W+ {. w+ C! `) l$ [4 m% y; Ccprintf("cursor position to the end of the line within the\r\n"); : b" w1 b' ]& b Pcprintf("current text window, without moving the cursor.\r\n"); cprintf("Press any key to continue . . ."); gotoxy(14, 4); getch();

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clreol(); getch();

return 0; } - s, k; ?+ n6 C

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函数名: clrscr 功 能: 清除文本模式窗口 ! |8 C/ I$ b. W& D" F, M3 O用 法: void clrscr(void); 程序例:

#include

int main(void) { " K0 X. h; P( R$ p6 j4 eint i;

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clrscr(); for (i = 0; i < 20; i++) ) \; d3 A* F5 y, @cprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); 2 t* L4 d1 F V8 |! r1 qgetch();

clrscr(); % D6 o* ~/ {9 c: Icprintf("The screen has been cleared!"); 5 X+ H. g+ ^1 h1 o, [5 V% k S+ q/ ugetch();

return 0; 8 y+ X+ ]- ^+ y+ }3 v# x} ! F% L8 |, n! I5 Y' X X" z # g& Q* h, a$ ]7 ^9 d/ k

函数名: coreleft 2 t. c5 w- x! V5 Q1 R1 H0 f- O功 能: 返回未使用内存的大小 % @: g# j% a& A2 b用 法: unsigned coreleft(void); 9 C# z* I/ J. J8 u+ J, A8 R程序例:

#include 9 Y" h# a/ I" S( a! m, e( {#include

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int main(void) { printf("The difference between the highest allocated block and\n"); * c; m1 H5 q7 e! {) I' Zprintf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; % ]- F4 v; a8 l% m: C. b9 G5 y( }( _}

函数名: cos 功 能: 余弦函数 8 J( s# S) l" \/ A8 g用 法: double cos(double x); + p; Y) v3 h4 V" L9 e" T' H$ F程序例:

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#include + \' H* R5 r& g7 b( O9 c#include

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int main(void) { 2 W8 g3 `" P. @6 p5 Q4 g; m3 tdouble result; 8 N$ E( U3 u" o7 P# udouble x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); - y2 u9 l* c( ^9 b2 y2 q6 `return 0; } ' ?$ h6 g; D5 {2 u7 ?' g+ C 4 l1 ?! T' j3 P7 D& D& P1 M$ B4 V

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函数名: cosh 1 N3 c# }% [1 g4 v* n5 I功 能: 双曲余弦函数 用 法: dluble cosh(double x); 程序例:

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#include #include

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int main(void) 2 A# |$ a! S* f0 f: ^9 g% Z7 d{ double result; double x = 0.5;

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result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); 9 E4 F5 M+ Z6 B2 o& f) b5 K) vreturn 0; # U4 ?1 }' o" c; A# e- X} 8 U3 h$ ?' b4 ^

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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); 7 \. r% X. f7 b! N$ Z9 C程序例:

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#include #include

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#define USA 0

int main(void) - [! m9 c: d' C a, V2 D{ struct COUNTRY country_info;

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country(USA, &country_info); ; ?. m( v ?* _, `. I6 J8 bprintf("The currency symbol for the USA is: %s\n", , c! I3 P+ l/ I- r7 mcountry_info.co_curr); 4 {4 k5 @: U7 q# m/ H+ Xreturn 0; } $ c+ O h* u9 C" j( J, A" x1 G

函数名: cprintf 9 T6 F# g1 f1 P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) , v4 D; D. v0 \$ `- u% z M8 ^# e{ % B, V' O, k( {8 ]/* clear the screen */ clrscr();

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/* create a text window */ X$ t. E% m" awindow(10, 10, 80, 25);

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

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/* wait for a key */ getch(); # j( r7 d9 `) l9 E4 ?4 g2 jreturn 0; }

函数名: cputs 功 能: 写字符到屏幕 用 法: void cputs(const char *string); 程序例:

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#include

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

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

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

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/* wait for a key */ getch(); return 0; } $ q Q7 o, Z2 b. }0 C8 L4 u

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函数名: _creat creat 7 x4 E' `+ T) P0 H+ m9 A: Y$ p2 q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); 3 j! R3 O( E: j程序例:

#include 3 y) f; E; G" F9 [* @+ |. m o8 }#include & C3 p# a$ V1 n9 o9 X- c0 c#include : o/ x* }/ g8 N; o t#include

int main(void) { % C- ^+ ]$ J; x1 |* ~' N+ j% A; kint handle; 6 }# ^5 B1 L3 R8 @9 d8 o2 u" t1 Tchar buf[11] = "0123456789";

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

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/* 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 */ " E) h6 c- G3 {3 x7 J& rclose(handle); 6 h$ c) t. Q4 \1 V6 B0 B. v: \' sreturn 0; } 0 C4 ]" L( _, r# s( Y/ R; y( f

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函数名: creatnew 7 W0 n) e# i! o0 b$ T功 能: 创建一个新文件 ' ?- ^' N1 c& G/ j4 g( B用 法: int creatnew(const char *filename, int attrib); 程序例:

#include #include ' `) }) [8 }% Z* I" H( |; ~. k#include #include #include

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

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

if (handle == -1) printf("DUMMY.FIL already exists.\n"); ! Z' P7 [# W1 D6 k' o& c, h; oelse { 9 Q2 B8 @ e$ d. n/ V% i* h$ G; Aprintf("DUMMY.FIL successfully created.\n"); 7 C6 Q- N+ b. wwrite(handle, buf, strlen(buf)); 9 p8 s2 o. Q5 Z7 v* o/ u W$ Yclose(handle); * r9 g! u! L# ]) P* t} return 0; } . g. b3 Y& E' y0 }. N1 Z" x" \* b: ? . P; [% t/ @. W# L

函数名: creattemp - G; f: X- e: P# t2 U, P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); " k1 A* q+ P) c4 e R0 l$ ^程序例:

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#include 9 x2 b0 ~( I" t, w, i#include #include

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int main(void) { ; ^% C5 V% A/ n% wint handle; / M$ b. Y; `! W+ K5 L* R9 d# n5 J0 qchar pathname[128];

strcpy(pathname, "\\");

/* create a unique file in the root directory */ ; R% _2 z- }, q7 i( i* Ehandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); ; ^2 {$ l7 t7 [6 Z% E w$ M5 C ]close(handle); $ t2 O4 d: L9 wreturn 0; } " x) I, K9 X0 V$ T+ _ , l6 z& e/ e M" g! v, u* h

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函数名: cscanf : ?' G0 g( P. v; M功 能: 从控制台执行格式化输入 / U) B4 O) ]* \% z* ^: p) k0 ?用 法: int cscanf(char *format[,argument, ...]); 8 Y( B7 ^7 [% ^0 h4 y0 b程序例:

#include

int main(void) l0 N0 B3 Q/ ~ j# r# C$ _{ char string[80];

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/* clear the screen */ + d& n" V, ^- q7 @! w4 r' [clrscr();

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/* Prompt the user for input */ $ y$ g/ Y* U6 d' ?7 E. p1 ucprintf("Enter a string with no spaces:");

/* read the input */ 7 ]$ w$ l' H# E; q- O4 I6 gcscanf("%s", string);

/* display what was read */ cprintf("\r\nThe string entered is: %s", string); % l2 O; L3 Y" n. x& i. kreturn 0; # ]% f0 y- r4 d/ |; r% J: j} " O5 ~& g& F3 O 9 t" ~2 i# I* I2 Z" Z& ^

函数名: ctime % I+ K t) r. ?) ~4 [0 z功 能: 把日期和时间转换为字符串 用 法: char *ctime(const time_t *time); , i4 L1 M1 D% F6 k+ f0 [程序例:

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#include #include

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int main(void) { time_t t;

time(&t); 7 k4 u+ R& r [" R# U: Jprintf("Today's date and time: %s\n", ctime(&t)); 5 G0 m* F# C& i+ s- G: preturn 0; 8 e8 Q: s' ] z6 t} 3 ^. ^2 X, ?5 @8 y3 W- }

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函数名: ctrlbrk , K8 O8 ]4 ^" ]2 g# z% C0 p功 能: 设置Ctrl-Break处理程序 / O' }9 ?# o! t0 S* S用 法: void ctrlbrk(*fptr)(void); # A# t: v% X5 b# ^( I' r% d7 Q程序例:

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#include #include

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#define ABORT 0

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int c_break(void) , G o# i1 |7 `9 v/ C{ printf("Control-Break pressed. Program aborting ...\n"); return (ABORT); 3 f0 i J; u; h* j& K+ {9 |0 t}

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int main(void) # V, Z r' g5 K6 m* m{ ' j- Q% r3 O$ h4 a+ fctrlbrk(c_break); for(;;) { $ \( f. `0 M9 W" xprintf("Looping... Press to quit:\n"); ( w2 U' G0 J* h' E% T} 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