函数大全(c开头)

韩冰

函数大全(c开头) ; i) E) K2 `' k

函数名: cabs # w# d* Z4 L+ }& k4 @. {# \; G功 能: 计算复数的绝对值 * I' ^2 [5 _* Y* t' j4 r* X7 G用 法: double cabs(struct complex z); ! w2 f' ?7 S4 v5 V' g5 C程序例:

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#include #include

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int main(void) 2 H8 e% V- u$ g# K5 _! t8 u{ 8 ^3 l: t& u" {struct complex z; double val;

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z.x = 2.0; z.y = 1.0; 7 @" n. p" ^* ]1 [ jval = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; 7 @1 O6 ^" Q! {# i# i7 }/ ]$ T} % V; x7 F5 ^' g. u7 ]3 T

函数名: calloc 功 能: 分配主存储器 5 _5 F$ t, L7 p用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

#include #include

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int main(void) * b/ V' k8 r% p! U& a) F{ char *str = NULL;

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

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

/* display string */ - y m9 n+ ]! R* W# @ t: _7 [4 Nprintf("String is %s\n", str);

/* free memory */ free(str);

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return 0; } 3 @# ]; x/ }. F+ I" U8 @/ z / \0 S$ s, U2 L# G' U& T

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函数名: ceil $ C" Q$ c, _1 y% s; n" \1 F4 W6 Q. a功 能: 向上舍入 / a- Q3 N" C* F3 s用 法: double ceil(double x); 程序例:

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#include #include

int main(void) { " _, W, E8 M/ T, Ndouble number = 123.54; double down, up;

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down = floor(number); up = ceil(number);

printf("original number %5.2lf\n", number); 4 f- u0 J% J$ g' _2 l( D% uprintf("number rounded down %5.2lf\n", down); # Q7 T8 c+ q/ H' x$ S1 M# gprintf("number rounded up %5.2lf\n", up);

return 0; } - ^, A% Z. e& q( U9 U* W 6 g( L8 p; Y- R7 x% \) J

函数名: cgets ! K5 g8 D4 y* q( k5 o& F功 能: 从控制台读字符串 4 e7 ^8 Y0 I- p. Y用 法: char *cgets(char *str); 程序例:

#include #include

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int main(void) 3 i4 B( W3 A0 r. k{ 5 _7 S! v2 T8 C, b& I! p3 ^# }5 Gchar buffer[83]; + C, O. t- Y/ s: r) d, [ Rchar *p;

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/* There's space for 80 characters plus the NULL terminator */ ! I% c' B- F! i5 m) t; A5 obuffer[0] = 81;

printf("Input some chars:"); 3 c% R% [+ M. }. f6 Q6 Gp = 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);

/* Leave room for 5 characters plus the NULL terminator */ buffer[0] = 6;

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printf("Input some chars:"); 9 }$ B+ @: g9 P2 a% F$ S) ]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); : H) u' J5 g Z$ E# }$ A' c( breturn 0; " f2 U, F( P8 M, E} 7 F, E) k. j/ n6 _( Q9 \

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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:

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#include #include 4 L8 A. ~% l; v% {# H% c* t3 ~7 d#include

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

int main(void) { % ~' Z" _" ]' a- q5 sif (getcurdir(0, old_dir)) { ( Z' }' R1 u! V, `perror("getcurdir()"); exit(1); $ M, x3 a, E0 t2 z} , e" z) R$ L+ [. W3 j1 G2 wprintf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) { perror("chdir()"); exit(1); 6 v3 l) x2 Q& M& x6 v( K! J}

if (getcurdir(0, new_dir)) { perror("getcurdir()"); * M! t3 w1 }" R: [$ Bexit(1); } ; n0 m+ A2 F3 n8 x r2 mprintf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); & Q9 l8 W$ S7 r+ gif (chdir(old_dir)) { 7 l, ]; z. R! p' tperror("chdir()"); $ C! c( J+ w/ _4 S% U1 `/ N: aexit(1); }

return 0; } - Z& b' d5 _4 ` + z: o8 J0 a j% v* @2 F

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函数名: _chmod, chmod 功 能: 改变文件的访问方式 - }4 O( R( n. X) {6 [' j! h用 法: int chmod(const char *filename, int permiss); 程序例:

#include : F X$ W; j$ S( G- T/ L0 K/ X#include #include

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void make_read_only(char *filename);

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int main(void) { / u% p: B& [, W3 z0 b" }% g |make_read_only("NOTEXIST.FIL"); 6 L; M4 F6 Z/ f3 mmake_read_only("MYFILE.FIL"); return 0; }

void make_read_only(char *filename) { " l) U5 H. [/ s% P+ z5 Q& aint stat;

stat = chmod(filename, S_IREAD); " j1 w5 e, u. t! @& |if (stat) printf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); 3 h5 t0 N5 U% R; B) L1 l} 3 l8 p3 K4 J: z, |: q2 ?

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函数名: chsize , I. m6 b# E7 M/ p- ^功 能: 改变文件大小 4 r" D+ v# {: ]( l' T. d* z# C用 法: int chsize(int handle, long size); 8 {# b7 A; H" ` p5 w程序例:

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#include " s& o) u. c% B3 L v \#include #include

int main(void) ' l6 Q4 i: k6 j, i2 \{ int handle; char buf[11] = "0123456789";

/* create text file containing 10 bytes */ ; L5 }. |. \0 } d. r3 N% Qhandle = open("DUMMY.FIL", O_CREAT); 3 q; W5 G# T9 b- n% h( y% ~write(handle, buf, strlen(buf));

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

/* close the file */ : q' ]+ K- @" Zclose(handle); 6 [' M& i: J' p$ g" _7 C7 Xreturn 0; } 8 V; X. f1 P5 u

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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); * c1 D/ S* v/ N' Q ?% _8 @. s, ]5 _程序例:

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#include ! Y' N% \0 z5 v l+ J#include #include % a3 \6 ?! [# c- G#include

int main(void) * K, g# J5 k3 t L( I; ]/ d4 l{ /* request auto detection */ int gdriver = DETECT, gmode, errorcode; - l4 |7 A' |" ?4 D- q7 d+ bint midx, midy; int radius = 100;

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/* initialize graphics and local variables */ / |/ L! y4 v: @# b3 _# r& kinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult(); / ]4 u- D' }' j& Q' z1 c0 }if (errorcode != grOk) /* an error occurred */ { ! B8 N: |! g/ hprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 5 @4 p }% }5 w4 c, }! Xgetch(); # g- Y. w* Z; K: _exit(1); /* terminate with an error code */ / M2 ?+ P2 y3 Y% ]) d8 I}

midx = getmaxx() / 2; 4 D( T/ M9 W+ Z3 o: c8 Umidy = getmaxy() / 2; setcolor(getmaxcolor());

/* draw the circle */ ! [+ Y1 O1 a6 ^; M7 }& {5 Icircle(midx, midy, radius);

/* clean up */ getch(); closegraph(); return 0; 2 n4 [2 {/ D- x5 T; c2 m" @5 O: |} 1 r' S1 }, A/ K/ B6 o

函数名: cleardevice 功 能: 清除图形屏幕 & P' ^; d6 m/ i% Q8 [% K; ]! T用 法: void far cleardevice(void); 6 O9 K. q3 v$ j- b* q: k e程序例:

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#include #include #include 8 f% T( X! C7 I- T5 W9 V. p#include

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int main(void) ; I* |- b4 O$ ~{ /* request auto detection */ int gdriver = DETECT, gmode, errorcode; ' W. e, V6 E* n6 k0 C" Fint midx, midy;

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/* initialize graphics and local variables */ ! j2 x5 J, x. j: kinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ % p; ~( E& Y& c6 X1 H+ @6 uerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ! O2 }, l- z# G* S0 L{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); 7 E: P! b2 U5 Y) J Xexit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; midy = getmaxy() / 2; 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 */ 4 q7 u9 c3 r' y: }# jgetch();

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/* clear the screen */ cleardevice();

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

/* clean up */ getch(); 2 B& k4 H' t) I! X" Q$ Xclosegraph(); / z$ o( S. }5 ]3 _! F6 ereturn 0; } 6 v8 }5 S; V r, {- n, T

函数名: clearerr . d: u" g0 Z2 o功 能: 复位错误标志 用 法:void clearerr(FILE *stream); 0 o L* x+ [' V' b. p ]6 S0 Q程序例:

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#include

int main(void) ( C+ f/ k q/ b/ X- G# O$ {: f{ ' s) o( P1 m3 I4 |" }& JFILE *fp; char ch;

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/* open a file for writing */ # r" d; p8 f# V# s$ U1 L' P" D; \fp = fopen("DUMMY.FIL", "w");

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/* force an error condition by attempting to read */ ch = fgetc(fp); printf("%c\n",ch);

if (ferror(fp)) ) c' Y% m: k/ h1 I' B/ l. Q{ /* display an error message */ printf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ clearerr(fp); 9 h; i6 D* V* D}

fclose(fp); 8 K) H3 i; z8 z( @5 V5 lreturn 0; } 1 y a" z7 H, c; `9 A7 u

函数名: clearviewport 6 ]# O0 b$ f4 t2 U9 x5 `, d* h$ W功 能: 清除图形视区 1 _* V4 S' s7 y4 w9 V用 法: void far clearviewport(void); 程序例:

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#include #include #include #include

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

int main(void) ; e6 N, c; E! L8 ]/ Y! J{ ) U. _ r( c$ B/* request auto detection */ int gdriver = DETECT, gmode, errorcode; , l" J: B/ h, }* X& u8 Zint ht;

/* initialize graphics and local variables */ % w- m- l! ]6 {( Jinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ . j1 P. ~% p9 U; j4 \5 Xerrorcode = graphresult(); ! S: h I2 z+ a# O9 A! M# jif (errorcode != grOk) /* an error occurred */ { 6 G3 j6 T2 P/ V( X8 N' t K- lprintf("Graphics error: %s\n", grapherrormsg(errorcode)); " J' p# T$ z. b2 I" q0 S1 a4 F0 X6 Mprintf("Press any key to halt:"); getch(); ( o! Y! L0 a7 i" t0 wexit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); 3 A0 L, g& u: bht = textheight("W");

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/* message in default full-screen viewport */ 8 T8 C7 [3 j) E" Q# Mouttextxy(0, 0, "* <-- (0, 0) in default viewport");

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

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

/* wait for a key */ 3 l# ~6 U S! C( N! |/ B7 s. q# J8 Wgetch();

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/* clear the viewport */ clearviewport();

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/* output another message */ 3 L4 K' N- Y: ~outtextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); closegraph(); return 0; } ; Q" ~) c4 A% X; z7 C; X 5 [6 @3 N7 Y- r" w$ E4 A4 _ ) u( f$ I# C5 _6 L, a; I/ F- f

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函数名: _close, close 功 能: 关闭文件句柄 用 法: int close(int handle); - X# d% ^& J1 f7 u$ B w程序例:

#include : C% e. F1 ]- f4 q: h5 B) s#include #include " M; L, o; y( u% B5 B+ m#include

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main() " H0 \ c4 x% L, b ?# Z4 O9 H{ ! `" P. P# ~# Z/ R% ~int handle; char buf[11] = "0123456789";

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/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); 6 n2 w( \1 e7 G2 aif (handle > -1) J- a; [# V, j7 D, N0 e: t2 j, H8 ?{ write(handle, buf, strlen(buf));

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/* close the file */ ) p g: c. i. g: Xclose(handle); } else ; a! r2 D- t( H: U{ * T3 x6 E( x0 u" T- \printf("Error opening file\n"); } % H: f a9 W" L2 j7 i, ?' nreturn 0; ! J, i; }5 v6 O2 g" d2 X} 7 a- w: r( M: {. n T% H: Z

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函数名: clock 1 h$ M/ y) `( O% @* z5 D1 F, T功 能: 确定处理器时间 - s2 t* Y! z3 d6 ^用 法: clock_t clock(void); - h6 n- D D* |程序例:

#include #include 1 l! M% m" F Z0 y0 h7 W# W/ b. e, [#include

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int main(void) 7 j8 v/ O! u- f{ clock_t start, end; 0 d B. a9 ^7 F9 j$ v; Ostart = clock();

delay(2000);

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

return 0; } 5 j- i+ @0 J# F$ m3 y

函数名: closegraph 功 能: 关闭图形系统 $ P% {$ v* I- q9 z! o: l( C& y" \用 法: void far closegraph(void); 程序例:

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#include #include 2 S$ _$ |% y8 j- A#include #include

int main(void) { # [* t' V+ U6 ]/* request auto detection */ 6 d4 m) ~4 v/ R' Y2 Sint gdriver = DETECT, gmode, errorcode; int x, y;

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/* initialize graphics mode */ . K+ D( f& ~/ }" Pinitgraph(&gdriver, &gmode, "");

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

if (errorcode != grOk) /* an error $ {7 A8 {' Q! X& c# p6 u% n* Woccurred */ l4 _3 G: V$ [( n- t7 ^* Q{ 6 P( A, M3 U4 H3 L! `' pprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); ( s5 Q. p d( H& t T2 Igetch(); ! x. i# J3 O$ Z0 b4 ~exit(1); /* terminate with an error code */ }

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

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/* output a message */ % [' i( e! S1 b$ f4 A" Bsettextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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/* wait for a key */ ; {4 |4 j8 h, E9 _getch();

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/* closes down the graphics system */ 5 j% x* V" X1 L3 d7 Nclosegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); ) {' ^6 e- V5 D0 [( P/ xreturn 0; + ?# k& \- c' z; ^. W} 9 W8 Z. H: V: y# _6 f- _" l4 U + ^) t" T4 G# T- I+ s

函数名: clreol - }4 H* a8 F0 g1 R5 I功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 6 {- \' [0 h: f# s程序例:

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#include

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int main(void)

{ clrscr(); * \# q; |' B# W# ?5 j2 r: E( rcprintf("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"); & x0 G. ^4 s: Y+ e9 j9 ?# W: Lcprintf("Press any key to continue . . ."); gotoxy(14, 4); getch();

clreol(); getch();

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return 0; }

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函数名: clrscr 功 能: 清除文本模式窗口 用 法: void clrscr(void); ) A+ D) n8 U7 Y& U# e V程序例:

#include

int main(void) , h6 L0 k" i9 g* y+ C{ + C$ ~( H% f+ p( Sint i;

clrscr(); for (i = 0; i < 20; i++) % P4 j% p! t$ F2 Lcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

clrscr(); + u' v5 a4 ?( U: o* t1 J& Rcprintf("The screen has been cleared!"); 4 X4 z( Y2 l- c: ?* C% i( J) |, Egetch();

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return 0; 7 w' o/ g, |& }' r& }} 8 x7 ]9 `* ?/ \4 W1 P/ `( F + t! c! Y2 }* W( ?4 D4 v . \5 ~0 x* ] W" D* j

函数名: coreleft 功 能: 返回未使用内存的大小 1 l4 j ?8 ^0 P) J) v5 O" \用 法: unsigned coreleft(void); 程序例:

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#include #include

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int main(void) & k6 Z; N5 m# H0 m1 j: r{ 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; }

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函数名: cos & R( D1 M- l0 _: |) y" r功 能: 余弦函数 用 法: double cos(double x); $ Y' D' }) Z$ c; d) T程序例:

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#include #include

int main(void) , t9 b; @/ @% N) R{ double result; $ I8 t- h n0 @$ sdouble x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); " A0 ~5 m( O" B- ireturn 0; } h' m% C" T: F1 m/ v$ G0 X ; M. ?1 O7 p! a ! j, h0 k2 X! q% s5 t5 `

函数名: cosh 功 能: 双曲余弦函数 # o3 E: Q* Y: @0 Q用 法: dluble cosh(double x); % v9 U% |' C, \, Q- O, }程序例:

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#include 2 o) w9 m" d/ K" O# p7 S$ i#include

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int main(void) ' k6 ~9 v7 j& b/ j) f{ double result; + q9 t5 K+ ^6 v" l+ Q1 Tdouble x = 0.5;

result = cosh(x); % k, d- w2 v" hprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; : X, Z* A4 B3 ?} : _4 }& G1 N* H- ]/ r' Y, W

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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); , A u7 m7 Z4 o2 V# ~- h4 r. e程序例:

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#include r- v9 k0 V r+ f#include

#define USA 0

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int main(void) 5 [+ W; b% i1 Y3 t{ 7 u" m# T! z2 R7 T3 ustruct COUNTRY country_info;

country(USA, &country_info); 3 V) ]1 |4 ]5 j. N4 c* Qprintf("The currency symbol for the USA is: %s\n", ' y1 W" {* L, C! s0 ]7 t1 s( Scountry_info.co_curr); return 0; 8 Z N: ~. x! i# Y} ; J5 s6 t5 K. r) S0 t/ V' V 3 J ?0 e! m' }& p. c

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函数名: cprintf 功 能: 送格式化输出至屏幕 2 l, }6 N4 u& B用 法: int cprintf(const char *format[, argument, ...]); . K2 U |$ p2 e$ ~% d$ Y- Z% v程序例:

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#include

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int main(void) 3 Z% L/ n; [# y{ ) Q$ o3 X* a. D4 |+ F/* clear the screen */ + R# y; s& y! e5 P, ]$ dclrscr();

/* create a text window */ 6 v8 N8 l2 I. K1 Twindow(10, 10, 80, 25);

/* output some text in the window */ " k% S3 A$ c% E6 @cprintf("Hello world\r\n");

/* wait for a key */ , p: u' X8 V! J( Ggetch(); 6 Y) |/ \' G( q7 q4 x$ L, Rreturn 0; ' Z' _) |- \! ~2 a1 }/ I& v5 v} # T0 T4 l& ?, N2 y. `/ c) Z* \! } : E" I' `8 }" `' `5 @

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函数名: cputs 9 ^5 `! X% ?8 n: Y0 ]0 x功 能: 写字符到屏幕 用 法: void cputs(const char *string); # r" ~3 x) M6 O: e2 t$ b程序例:

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#include

int main(void) { 1 `0 H$ g6 @2 Q7 w$ Z' D/* clear the screen */ clrscr();

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

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

/* wait for a key */ + t7 J8 E# W# ^, Pgetch(); return 0; } ! ?7 f7 k& d+ X6 R: a1 w ) `$ F5 c! Z, b7 _8 y: O' ]$ p6 D

函数名: _creat creat - f( H3 e3 A$ f y/ L! r 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); 程序例:

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#include #include 0 R/ `' s3 Z+ ~3 U#include ) o" t5 f$ Q& k _% H#include

int main(void) " D8 F& C$ ^( n( G/ {: q{ int handle; . r4 S' Y1 n; @$ U& g3 L0 rchar 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 */ * o7 E9 V; w) f1 c& u: Fhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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

/* close the file */ close(handle); return 0; } / x. D) b; e1 U$ F, A

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函数名: creatnew % l' H' Q6 a, j功 能: 创建一个新文件 $ }6 {7 r: g8 u用 法: int creatnew(const char *filename, int attrib); ) k: \+ U* T# i7 {' i& b程序例:

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#include #include % R& n' \1 p _( }* x#include , h. `( n# ?( q" r( u#include #include

int main(void) * G' I7 [0 N$ ?/ B6 `2 B{ int handle; char buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ " |1 |) Z/ `1 s3 Bhandle = creatnew("DUMMY.FIL", 0);

if (handle == -1) . P% F o) s4 Rprintf("DUMMY.FIL already exists.\n"); else { ' J x2 W' o6 M, m+ K* U2 Jprintf("DUMMY.FIL successfully created.\n"); 2 U$ |" r7 u- I, f- F- F" S! R' dwrite(handle, buf, strlen(buf)); - f# U' S7 M# x* ~close(handle); } return 0; } ( S) w9 ?! g2 i

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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 用 法: int creattemp(const char *filename, int attrib); 程序例:

#include % E5 k2 b. v! [: y g" @% D#include 6 M, _0 d$ ^$ K- ?* e#include

int main(void) { , d) m8 _, O+ F1 \+ w, r# {* B7 x. Gint handle; 4 l5 @ W5 D+ h' W1 ^2 i+ ychar pathname[128];

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strcpy(pathname, "\\");

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/* create a unique file in the root directory */ ( E- B) _' v; B, Q7 t/ i# {- E( J/ U5 Qhandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); . {* I' Q5 C; X1 gclose(handle); return 0; } / M. w b/ v$ D3 x& R & q& ~ l# _- z a' b

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函数名: cscanf 2 w+ t3 Z; _+ \, T功 能: 从控制台执行格式化输入 # [ F4 `2 @& p9 _, X用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

int main(void) { % I- n- a3 n( ]) C8 Gchar string[80];

/* clear the screen */ clrscr();

/* Prompt the user for input */ * l2 }2 T- G7 f% w M, v/ Z) icprintf("Enter a string with no spaces:");

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

/* display what was read */ % e2 y W: {6 f1 f3 n- p; _: v# n$ gcprintf("\r\nThe string entered is: %s", string); 2 n1 m# G: G% P [return 0; } * d- i7 D6 m( M3 e% v

函数名: ctime ! Q# Z: ~" R1 P- a9 X功 能: 把日期和时间转换为字符串 . M( e7 T* h" b) H# m+ f用 法: char *ctime(const time_t *time); 程序例:

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#include F5 `) x# Y6 M' G4 e9 l#include

int main(void) t% F g, e4 }- i( I$ Y1 i( A8 _{ . i3 i) _: I" r2 o$ Wtime_t t;

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time(&t); 2 T4 C. N6 B9 x: Lprintf("Today's date and time: %s\n", ctime(&t)); return 0; } 3 H" Q. _- D2 V4 P8 b0 E6 b4 r ' b3 F. H8 [& f% S; ]: G

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 3 T" S; s; s6 T' a) d3 x' K程序例:

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#include #include

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#define ABORT 0

int c_break(void) ( O6 P! k$ f% [, [4 u{ printf("Control-Break pressed. Program aborting ...\n"); return (ABORT); ( h6 V% w5 b# G" G+ P! {6 o}

int main(void) { , J) x0 Y' O, I4 ?ctrlbrk(c_break); for(;;) + ]2 V/ m* [- F9 S) s{ 8 [( g/ U$ c+ R7 b4 v) Jprintf("Looping... Press to quit:\n"); } : R2 t, e f8 S1 q5 j5 nreturn 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