函数大全(c开头)

韩冰

函数大全(c开头) , W" B& m/ T" I& u7 Y0 ?, T# I

函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); " v6 b& c1 ?# I+ u2 u程序例:

#include & Y7 S: M7 M* q( k#include

int main(void) # w: q0 K! [. T& {{ % e/ A4 f- u1 B, U% d4 e1 h, ~( nstruct complex z; & U& o7 }$ @4 k3 gdouble val;

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z.x = 2.0; 4 ?( p8 a. q0 i% A6 ?z.y = 1.0; , e9 t; Q# s( s. N" t Bval = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; } ( B; `! G8 l7 v. _ 1 N1 m7 Z0 W4 g) w 2 H5 M4 k( J2 Q7 I0 T( t3 n! m

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函数名: calloc % x9 O( o* p1 M3 H/ b* D; Y9 E- {% Q功 能: 分配主存储器 }& j, U# p4 D% j8 n5 ?" @用 法: void *calloc(size_t nelem, size_t elsize); + W6 H7 l# t: h# i ~ k/ ]) Z程序例:

#include #include

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int main(void) { char *str = NULL;

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/* allocate memory for string */ / c- y! v! B7 Rstr = calloc(10, sizeof(char));

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

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

/* free memory */ ) V; e. D6 J' {$ s' I% D+ j7 Kfree(str);

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return 0; } ' O: F" B% Q4 V2 S/ A

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函数名: ceil % q. W1 @0 S) g$ x T" v功 能: 向上舍入 ' I( U I4 h |. o. ], ~用 法: double ceil(double x); 5 y3 v6 h: Q1 D6 T程序例:

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#include $ ^8 [* Y; ?8 z0 R1 ^. l#include

int main(void) : _; H2 a1 D" j{ ! l0 c' N" w$ f& m) j& A0 Kdouble number = 123.54; 2 U3 D* M' e( c# edouble down, up;

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down = floor(number); ! r7 p% o* Y9 A; i6 `& i( R/ Wup = ceil(number);

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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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函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); 程序例:

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#include #include

int main(void) 6 U7 J8 O6 M* A- \{ char buffer[83]; / F6 o4 |# |, ]5 s( i" C1 ochar *p;

/* There's space for 80 characters plus the NULL terminator */ 6 q- Z3 {3 J8 N2 |buffer[0] = 81;

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printf("Input some chars:"); 7 s& m9 D- y) e9 cp = 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);

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/* Leave room for 5 characters plus the NULL terminator */ 0 F( B% c; J7 T. Vbuffer[0] = 6;

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printf("Input some chars:"); . F. d2 F! {! s5 A' f0 ?0 X1 ^+ [2 ?7 up = cgets(buffer); , M+ s* |5 N& ?! M; {( yprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 0 t3 y& z5 Y: V/ U1 k% U! Eprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; } . J2 A7 S- w: o* S2 u d& V3 m, z

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函数名: chdir 功 能: 改变工作目录 用 法: int chdir(const char *path); ! R9 B* I& J2 B5 m程序例:

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#include 5 t3 H w! u. p8 d4 ~& Z#include #include

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

int main(void) 5 r$ a! l5 _3 @: z5 J" G' p: c{ if (getcurdir(0, old_dir)) 3 _$ L* n `5 G8 _& S{ perror("getcurdir()"); 5 |- `4 Z! j. d' W5 r9 I! W* Pexit(1); } printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) { perror("chdir()"); exit(1); # b+ k$ y8 ?- j1 v% u}

if (getcurdir(0, new_dir)) { perror("getcurdir()"); 7 ]6 d% p9 u9 D+ u& H4 Jexit(1); & e& `6 P1 w" d6 _+ h `} 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)) { perror("chdir()"); exit(1); }

return 0; 4 D" Z7 E1 R+ p; B9 Y e8 J} 9 J- A7 |. f. Z# s; J

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函数名: _chmod, chmod 4 R! v& i% {6 ~ J( _3 V. A功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); 程序例:

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#include 0 F, }- B" U) B y: ^#include 4 y7 P; U& m0 r: v- I+ f0 ~#include

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void make_read_only(char *filename);

int main(void) { 7 c9 }4 C+ e, _' [( `make_read_only("NOTEXIST.FIL"); $ |3 i% ]' G- V+ Wmake_read_only("MYFILE.FIL"); return 0; ) X m" _2 }& ]4 F, q0 d. v}

void make_read_only(char *filename) 8 ]9 r `1 H4 M' `( ~* b* m{ int stat;

stat = chmod(filename, S_IREAD); 1 w* S3 j' X7 W0 ^9 v$ s# y/ w g" V! xif (stat) printf("Couldn't make %s read-only\n", filename); else $ K/ O: p/ C Tprintf("Made %s read-only\n", filename); }

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函数名: chsize 功 能: 改变文件大小 用 法: int chsize(int handle, long size); . U# S" k4 ]5 j程序例:

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#include ' o4 c: i% l+ ]#include . {+ ]4 O% O' a1 G6 } Z2 Y#include

int main(void) { ; j* P$ s s U% D: u- M* D* H: xint handle; / y- \2 r7 O/ `: ^char buf[11] = "0123456789";

/* create text file containing 10 bytes */ ) S3 ?, t8 Z; m3 H1 @* K# j$ }handle = open("DUMMY.FIL", O_CREAT); 6 M, w! I9 \$ A! {+ L' K. bwrite(handle, buf, strlen(buf));

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/* truncate the file to 5 bytes in size */ * E" a3 o5 x" v) k2 m0 Echsize(handle, 5);

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/* close the file */ 7 r8 l. g1 E5 xclose(handle); return 0; $ ~; [$ y* y8 D( N; d}

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); 程序例:

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#include : z+ T9 h, A: W# E2 Z2 _' y. D$ F9 w#include - q5 {0 G4 Y5 w) I) {; T3 ]#include 7 Y2 F1 N4 I8 j+ A' s#include

int main(void) { 1 z2 X8 U5 ~3 }% M" K4 }; Z/* request auto detection */ # v0 I1 A) Q% y; Zint gdriver = DETECT, gmode, errorcode; 6 q \ l3 ~. Q3 g ]1 Dint midx, midy; int radius = 100;

/* initialize graphics and local variables */ * b1 L& j. ^! D- \% }9 Uinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ & R& m2 ]5 m) \2 A2 @- i W' gerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ( q2 U t* ~: k( o" b{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); # }/ v' A3 @* s0 H: i: x: ygetch(); ' ] }* s8 z zexit(1); /* terminate with an error code */ & y+ F4 Y0 w7 y4 x* C" K" N0 j}

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

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/* draw the circle */ circle(midx, midy, radius);

/* clean up */ getch(); closegraph(); return 0; |% ?$ e# a/ W3 {8 C; j8 h} ' N* b) L$ ~: \! ]; v

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函数名: cleardevice ) F" j) f6 ]7 k C功 能: 清除图形屏幕 - \$ a, Z( z# s" y8 q用 法: void far cleardevice(void); 程序例:

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#include #include 1 I# Y3 J. s! X" q( @* w9 E#include #include

int main(void) : w- g7 y2 j m$ `4 S{ /* request auto detection */ " E; m& J) ?0 N. A6 Y9 a. nint gdriver = DETECT, gmode, errorcode; & s. E! k1 u G0 [int midx, midy;

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

/* read result of initialization */ / \9 ~1 T- L# {errorcode = graphresult(); 7 Q9 Z1 c- }/ R, e Y0 U3 Fif (errorcode != grOk) /* an error occurred */ { & e$ f7 x Z! x% ]& j2 Dprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); ! O5 ^/ n5 | r9 n' D, s, {% @exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; midy = getmaxy() / 2; $ R9 O; L$ Z5 O2 ~) g" X9 l* }setcolor(getmaxcolor());

/* for centering screen messages */ : L8 L" n" A" [; Osettextjustify(CENTER_TEXT, CENTER_TEXT);

/* output a message to the screen */ 6 t5 Y% U+ b# m: v6 I& \outtextxy(midx, midy, "press any key to clear the screen:");

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/* wait for a key */ + A5 {! B5 j& ~ O! ?getch();

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/* clear the screen */ : P6 S* l$ }. r0 w+ s, P4 p: @' rcleardevice();

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

/* clean up */ 6 e8 t' P" A- q* Wgetch(); closegraph(); return 0; @. o3 d3 O( I0 u0 j# j} ; {+ f7 J9 v( y- o4 I

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函数名: clearerr ) W' F6 [9 K) Z3 o8 ~功 能: 复位错误标志 + x: u2 f- o6 I用 法:void clearerr(FILE *stream); : `; H1 Z& }; R0 ~4 ]程序例:

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#include

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int main(void) { FILE *fp; " q/ u' b u4 s4 B9 \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 */ . U4 P0 a* o' ]$ N2 m: R' `ch = fgetc(fp); ) \6 M4 F8 K; q( p; N9 j0 ~: w9 _printf("%c\n",ch);

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if (ferror(fp)) w+ R6 ]! I- a; o' p6 M8 u{ /* display an error message */ : q% p1 ]7 f; I8 q) t7 f4 `, wprintf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ clearerr(fp); $ F/ Z$ E' _ O% K1 q}

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fclose(fp); 1 J9 i/ }' {+ Q5 |! Treturn 0; 3 b) k. f9 ?5 M" U+ X. w}

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函数名: clearviewport 功 能: 清除图形视区 * p5 [9 L9 K' d& D用 法: void far clearviewport(void); % n) |4 }9 [4 M5 W$ q! H程序例:

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#include #include 0 _) d. |9 H8 G0 x$ b w% P8 x3 y9 u5 D#include #include

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

int main(void) { 6 p% M8 D4 X' T, ~/* request auto detection */ & N8 D) L. r3 |1 jint gdriver = DETECT, gmode, errorcode; int ht;

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

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/* read result of initialization */ ; G( @7 S: Q5 T3 W( Q2 l, ]+ ^& Jerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { % O; G/ D1 d0 F. rprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 3 f- F8 J: v% F4 I, zprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 3 _# A) B, B; I# |# a# N) \}

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

/* message in default full-screen viewport */ * K) h T# e, d6 Douttextxy(0, 0, "* <-- (0, 0) in default viewport");

/* create a smaller viewport */ # d. X5 G' t1 T c9 P& ~* ~, Msetviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON);

/* display some messages */ . a) V. f7 q# X% i* C1 M* Souttextxy(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();

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/* clear the viewport */ 8 Z( H% ]4 k% [8 x H! K. r8 pclearviewport();

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

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/* clean up */ * E2 ]' q; y5 ~$ ^' x. [ M) bgetch(); closegraph(); return 0; }

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函数名: _close, close 功 能: 关闭文件句柄 # n) i2 ?% ]: O$ l, R" t用 法: int close(int handle); / b" F( z; X2 z- E6 L程序例:

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#include #include #include #include

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main() { int handle; + I. p% y" K9 z; xchar buf[11] = "0123456789";

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/* create a file containing 10 bytes */ & a0 r+ _8 F- p7 _! Ohandle = open("NEW.FIL", O_CREAT); if (handle > -1) { write(handle, buf, strlen(buf));

/* close the file */ " l. ~& _9 j$ |: Y& v4 rclose(handle); / k+ d' h; e5 R" Z} % J0 h( Y: B* r% }else { 9 \% V1 l' j1 ~# ]; n; yprintf("Error opening file\n"); 5 x4 F$ l; D: ]+ q) Y. O} " v) y/ N0 v { I kreturn 0; / W& a" x& ~/ R6 U7 E& S9 v# e& C! c} 0 p+ y/ h, C8 O& o

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函数名: clock ) ]9 @' n1 u- u0 t) y4 ^功 能: 确定处理器时间 - H# h+ @) I' {! t1 q- h用 法: clock_t clock(void); 程序例:

#include # q# Y+ J. l: ?% \; y3 ?#include / f7 j2 C) \+ ~2 z#include

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

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delay(2000);

end = clock(); ) _$ U+ m2 x$ cprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; & a( z. L6 }9 s1 g! O9 E6 |} ( i/ v8 p. y9 O ; y5 n% @# L" Q3 Q

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函数名: closegraph 功 能: 关闭图形系统 用 法: void far closegraph(void); K! [8 y0 Y8 y. O3 t- S0 M' F/ E程序例:

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#include % C8 `# \. z" ~' @% j1 `#include ; z6 x; q% i# A2 ]3 i( Q#include #include

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int main(void) 8 M* _5 m2 k. k{ . _, o" h! F/ H) e6 o) _/* request auto detection */ int gdriver = DETECT, gmode, errorcode; " J, N7 @: R9 m7 e3 r5 }: T8 b; @int x, y;

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

/* read result of initialization */ ! i9 V2 z) k% z0 }: D* Q U/ ]/ }errorcode = graphresult();

if (errorcode != grOk) /* an error + B( G8 d. p( w. ]occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); ( h/ c# J) v4 g3 [$ ` [ Rprintf("Press any key to halt:"); getch(); 1 _% \5 H1 R; c: w& R, i3 `. oexit(1); /* terminate with an error code */ }

x = getmaxx() / 2; 7 ?8 L4 O) f2 b* G1 Xy = getmaxy() / 2;

/* output a message */ # d m6 S% a3 _. ?settextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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/* wait for a key */ * h" y, _+ ~1 B+ }getch();

/* closes down the graphics system */ 7 ]8 g" O2 b; R/ ?" `' \# g4 Jclosegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); * c4 r+ d9 Q% {3 p: n0 d2 p6 \) kgetch(); * L; V! a7 I! D1 J) Greturn 0; / r0 h0 b2 |8 |+ C} ; w% w* a: j% E7 B" o2 o8 g3 \ J3 B" y( p$ ~- E1 G0 n" Y1 [

函数名: clreol 功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); * k0 L7 k3 P9 G6 `% D0 X6 g: Q程序例:

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#include

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int main(void)

{ clrscr(); cprintf("The function CLREOL clears all characters from the\r\n"); ) L2 L, ~, A4 V F6 wcprintf("cursor position to the end of the line within the\r\n"); 5 M! E4 ?1 }) u+ F% a mcprintf("current text window, without moving the cursor.\r\n"); * H5 n' a' y- Ocprintf("Press any key to continue . . ."); * j; E7 S+ |* y ? Ygotoxy(14, 4); getch();

clreol(); , S1 p) I5 x) E# r$ [getch();

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return 0; } 0 X" J0 b& Y& t# s8 K* M

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函数名: clrscr , [' R& b$ |% A' I: {# c功 能: 清除文本模式窗口 用 法: void clrscr(void); 0 x0 w) A+ ~9 j' v5 Q( T程序例:

#include

int main(void) % |9 H( J; w4 G0 J7 e) f{ int i;

clrscr(); for (i = 0; i < 20; i++) + F- b( k* _. |& D# Acprintf("%d\r\n", i); 6 b; B2 @& e4 J! K$ P! s. Q1 T; Z2 U0 Acprintf("\r\nPress any key to clear screen"); ' c3 d, D. | E; L: d$ {# Cgetch();

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clrscr(); + N$ z$ z) a( l+ G2 gcprintf("The screen has been cleared!"); . S' B' L5 L! I" I o- F* F8 b3 l0 Wgetch();

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return 0; ; _# @' y, n( [} - c3 D- ?0 C- R2 u& P7 S3 ?4 |3 Q ; \% A" w" k2 M$ B+ G

函数名: coreleft 功 能: 返回未使用内存的大小 - o$ h7 h1 ]" q+ w用 法: unsigned coreleft(void); 5 l' \; P2 f! Z程序例:

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#include 2 E3 \" Y3 `; ?6 y& r" @#include

int main(void) ' O; g& y! \- J# @$ _' v# g# `& o- I{ printf("The difference between the highest allocated block and\n"); printf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

return 0; }

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函数名: cos . K" G8 ?9 L& ^0 |! K功 能: 余弦函数 5 F+ O% a- p E3 x用 法: double cos(double x); 程序例:

#include $ r1 e( D& j7 e p#include

int main(void) { , c6 x; W" Y8 R; Gdouble result; double x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); 3 G, ?5 ]( ^! n" Areturn 0; }

函数名: cosh 1 u0 a- P' m# q. g+ n功 能: 双曲余弦函数 + }. y [ L1 ~7 S. L* R |' P用 法: dluble cosh(double x); 6 q# p1 L3 U7 [, Y7 G程序例:

#include #include

int main(void) { double result; _1 ]8 I$ I6 S {' {+ \* q+ W/ L7 Gdouble x = 0.5;

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result = cosh(x); ) r1 s3 E; b0 G3 }3 wprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; } 3 ] ^0 O# x0 T! R 4 I5 }. ]# j6 I( z

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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); 程序例:

#include #include

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#define USA 0

int main(void) ) [5 Z, ? q$ |1 s{ ; m H" |4 a/ m7 q! ]+ ~; W" Istruct COUNTRY country_info;

country(USA, &country_info); & A- B# v" s$ K! C1 K; r# \5 |printf("The currency symbol for the USA is: %s\n", country_info.co_curr); return 0; } & {! F, f$ O1 l5 }+ ]

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函数名: cprintf 功 能: 送格式化输出至屏幕 0 o& ~5 g d$ t0 A# s, j用 法: int cprintf(const char *format[, argument, ...]); 2 q4 W( L* o& \ [6 G+ M程序例:

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#include

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

/* create a text window */ 6 _, |- o) h' h# N5 S9 bwindow(10, 10, 80, 25);

/* output some text in the window */ " k2 p7 q: i% T: I* i' Y! {cprintf("Hello world\r\n");

/* wait for a key */ # _) B0 D: G1 ygetch(); return 0; } ( Y6 o. c. Y* _& \# l# A; L

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函数名: cputs 功 能: 写字符到屏幕 ' f1 y' O3 |% u P; d* M用 法: void cputs(const char *string); 程序例:

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#include

int main(void) , x; B! B1 J. ]% G" h4 V- J! j{ /* clear the screen */ $ T: u* Q% j _! Q+ |1 _# `1 Sclrscr();

/* create a text window */ 9 L0 o) k! z7 ~' o, U9 _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 */ 7 N; _' M, @: Cgetch(); return 0; } ' M# i$ P# F m3 n2 ]6 N! @: R 6 h8 B" }- ]1 T9 H# |

函数名: _creat creat 1 q4 I: u! O; I功 能: 创建一个新文件或重写一个已存在的文件 ( R( E! [" I9 l用 法: int creat (const char *filename, int permiss); : N, \2 y6 m! U& a! a程序例:

#include #include #include #include

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int main(void) 3 \6 m& G' h+ O* Q0 R) k{ int handle; char buf[11] = "0123456789";

/* change the default file mode from text to binary */ % t, o; @& f6 Z" __fmode = O_BINARY;

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/* create a binary file for reading and writing */ & H4 \3 A* b, s8 g' [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); return 0; 5 K. Q; [, ~# Z: @% x}

函数名: creatnew / \3 U9 |; b% z- ^功 能: 创建一个新文件 ! X; n( u. {: ~3 u+ p. E用 法: int creatnew(const char *filename, int attrib); 程序例:

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#include #include #include , R1 A8 p7 M2 K+ ?+ [7 ?#include #include

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int main(void) { 7 X$ Z B% w" N4 b/ W4 t/ ~int handle; + M* h, f3 {; p7 schar buf[11] = "0123456789";

/* attempt to create a file that doesn't already exist */ / t2 j( y1 Y3 j- nhandle = creatnew("DUMMY.FIL", 0);

if (handle == -1) 4 r* ^3 w# [* `" Y6 _4 a; V( g0 eprintf("DUMMY.FIL already exists.\n"); else { ' W4 g: _6 \! X: e; t6 f/ }printf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); close(handle); / H5 ]# X9 h$ }. K} , T6 } L& f# G; `$ Hreturn 0; , [+ g$ G9 w& }. c2 I7 d3 ]& r} 3 f) [8 ?% a, B" b Y0 y

函数名: creattemp ) a' ^" ^! ?* Y$ R2 s( z功 能: 创建一个新文件或重写一个已存在的文件 2 F" t; G5 u( b- ~% S+ Z用 法: int creattemp(const char *filename, int attrib); 程序例:

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#include #include ' ^4 z" L+ k3 P( l( h#include

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int main(void) { int handle; 0 ~3 a. g! D0 G9 E) Fchar pathname[128];

strcpy(pathname, "\\");

/* create a unique file in the root directory */ ' R( F h+ {# @handle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); close(handle); return 0; % x+ [7 P3 m" v" i. p1 q} 5 N2 H7 D8 ]' R* p9 B! O

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函数名: cscanf 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

int main(void) 9 s0 V. J1 Y, C' y7 a9 c5 _& \{ char string[80];

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/* clear the screen */ & ~6 e& z6 a1 G6 I2 }clrscr();

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

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

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/* display what was read */ 4 g0 }( W. I! I: m! t: k) ~+ l" tcprintf("\r\nThe string entered is: %s", string); * a/ U! n/ H& J( N7 y$ a' \) nreturn 0; ) Y% u$ x5 }1 o' w} 7 m7 q, b3 v# I5 b! s$ F f $ J( L4 E# b0 \! \( X q: e( r

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函数名: ctime 功 能: 把日期和时间转换为字符串 * P J( V. h3 f# L& ^用 法: char *ctime(const time_t *time); 程序例:

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#include #include

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int main(void) $ `+ Z/ X) _' ~) a7 Z! f. w{ 3 F k6 B, F0 [+ Ztime_t t;

time(&t); 2 k' A4 v6 s3 h6 m) Z9 Yprintf("Today's date and time: %s\n", ctime(&t)); . Z; t. C% Z2 P! J7 mreturn 0; & i: ~* J0 y+ f, ]- m7 R" k3 _. D9 D9 ^} ; z' h$ B; Q+ E9 y. D- b

函数名: ctrlbrk 0 S- }2 V( a1 H% z' c$ ~功 能: 设置Ctrl-Break处理程序 8 b3 u1 }9 G# p8 F用 法: void ctrlbrk(*fptr)(void); 程序例:

#include 2 E# e( i7 _/ Q#include

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#define ABORT 0

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int c_break(void) { , K; u9 q9 b3 E9 J3 ~' ?! Wprintf("Control-Break pressed. Program aborting ...\n"); 7 j$ ~3 I5 C: C- [5 ]! x, Rreturn (ABORT); }

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int main(void) { : ^% l! Y. `) v; yctrlbrk(c_break); for(;;) - j% G2 B; k0 @& X8 E( b{ 5 F3 M$ t8 g; p$ {8 {9 Wprintf("Looping... Press to quit:\n"); } ; N4 r# r6 d6 t' S8 n8 y/ H) p. A# kreturn 0; ( y E3 H6 ]; b}

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