函数大全(c开头)

韩冰

函数大全(c开头) . B0 l' g; l/ T. {4 j# D1 m

函数名: cabs 功 能: 计算复数的绝对值 7 w! c& j" w% X用 法: double cabs(struct complex z); / W8 P" x2 X/ d! O3 W" g程序例:

#include 4 J0 R2 C8 S! V8 V; G: t#include

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

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z.x = 2.0; z.y = 1.0; val = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; - C6 l0 T: Z" Z3 P/ R4 n} : ?. G2 k' k5 q: ]5 } ' p$ z6 U9 Z7 {+ L

函数名: calloc w: a0 O. O! N I1 G功 能: 分配主存储器 5 A& j" \7 @. J/ K( F用 法: void *calloc(size_t nelem, size_t elsize); 7 G" d( z9 W/ L! Q8 ?, H程序例:

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#include 1 U7 [, v4 F; W9 U& o. C* e#include

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int main(void) 2 u. W3 n( t( b" t% o{ char *str = NULL;

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

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/* copy "Hello" into string */ ( C0 J! [' U2 k) s# v6 g6 o- u/ ?/ Kstrcpy(str, "Hello");

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/* display string */ 1 l A) K# N" s6 X& ?printf("String is %s\n", str);

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/* free memory */ free(str);

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return 0; } 8 t# M6 l y- X- k, Y# }

函数名: ceil 功 能: 向上舍入 3 V; Y- n0 {8 X用 法: double ceil(double x); 程序例:

#include #include

int main(void) % i5 N2 z% m( v! h: Z& e( S{ 5 @. @) d# H1 A7 r* `, edouble number = 123.54; : C& B3 X5 W( C) a+ u/ C _double down, up;

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

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printf("original number %5.2lf\n", number); 6 A4 P% j% |- H7 ]printf("number rounded down %5.2lf\n", down); # e7 X3 z' f& s8 p4 e3 y" Wprintf("number rounded up %5.2lf\n", up);

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return 0; 6 c& `/ ]' ^7 o4 K" @: u) F, B/ m} " Y& G3 R t$ `3 [ ' L& o4 ?: r3 A, V5 a* i; `9 q & P; E' K/ L, {0 s4 l& P

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函数名: cgets 7 Q9 f8 N: t8 T" H, ]功 能: 从控制台读字符串 " \ ^$ C0 ]+ S/ i5 k1 _% t3 G+ l0 p用 法: char *cgets(char *str); 程序例:

#include #include

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

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

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printf("Input some chars:"); 0 _. V% o+ f7 t8 d9 [p = cgets(buffer); , S2 \. B G9 x3 Pprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 1 `' L2 @) G9 |9 @* }4 L$ n( Rprintf("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 */ ; u" b; W" d! @; Ibuffer[0] = 6;

printf("Input some chars:"); . w4 M) M% R, l, ^3 G+ E' I. {p = cgets(buffer); 9 E3 }5 [7 N8 u5 i3 Tprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 4 w: C* @8 {" q$ e# B+ X* |; fprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; * N2 H" F1 Y2 w) w4 T} . u. m) `, q4 p" S }* J

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函数名: chdir 5 m5 f1 h6 m+ g& i功 能: 改变工作目录 用 法: int chdir(const char *path); & A+ N5 |. P4 Z K7 G& x% g程序例:

#include ) W+ E6 x9 C9 t#include #include

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

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int main(void) { , v+ i6 P- E5 Q& M+ M$ X8 Vif (getcurdir(0, old_dir)) ) R% I1 ?8 ~6 ?9 [! T/ F, T3 K{ : g7 q+ @, L, @" J- c: ?; P( @perror("getcurdir()"); exit(1); 0 t( Z3 z- j) z% Y+ _1 ? p} printf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) { perror("chdir()"); exit(1); - N& p7 x; m, x+ I}

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if (getcurdir(0, new_dir)) & v6 x( s* e. e; r9 `. A0 w3 u{ " C. M- t* ]3 jperror("getcurdir()"); 0 o" y$ D5 o3 z K5 zexit(1); } 8 j8 |7 E# R- m* w+ ^printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); W* g* P* w2 ~if (chdir(old_dir)) { 6 i7 N4 F5 D1 q u/ wperror("chdir()"); exit(1); }

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return 0; } $ @, x, W8 n0 `8 R0 ^ l9 G3 k$ } % [! F. x- Z! {

函数名: _chmod, chmod 3 y4 P+ v( B7 N0 D) E功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); - x# y/ H) W$ K, f/ r& `5 @ i$ r) v) `程序例:

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#include #include ) e0 j7 G; e# v9 O" \% R9 T#include

void make_read_only(char *filename);

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int main(void) { make_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); " b- [: ^+ D) X: L: O6 ?return 0; # i( E3 {8 Y; \- h}

void make_read_only(char *filename) & }& [5 o" j/ x* |& I% C2 l# e{ 6 U; ^, g6 _' H2 h; Z& b6 _2 Aint stat;

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stat = chmod(filename, S_IREAD); + g2 k" _% q7 [3 r( K& O9 Zif (stat) 7 j) R) B3 o1 p* b9 E7 _printf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); ; ^* [' ^7 U" {+ C1 _} & q+ g0 l& E( p

函数名: chsize 3 c# Z* T$ b A6 {4 M功 能: 改变文件大小 用 法: int chsize(int handle, long size); 程序例:

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#include 7 |6 S- D3 v- L- a& o0 P- U$ s$ H4 q#include #include

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int main(void) & u* ~" |! g; }{ int handle; : w! |9 F- Z, C& f7 \& } ochar buf[11] = "0123456789";

/* create text file containing 10 bytes */ handle = open("DUMMY.FIL", O_CREAT); write(handle, buf, strlen(buf));

/* truncate the file to 5 bytes in size */ $ ? {# \: d" g& Rchsize(handle, 5);

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/* close the file */ close(handle); 7 Z7 P" Z) H4 q) {3 ^ \9 g4 H8 yreturn 0; 5 z/ G* V8 L& F2 A- L}

函数名: circle ?! }6 J, P( w" M4 L: 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); % @# Z: M. h9 G7 l$ ^程序例:

#include #include #include 7 j# N) m2 b, c! }( \#include

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int main(void) * l j! _: V2 W# r/ u# t, X{ /* request auto detection */ 6 U) |* D% _( l9 m7 Mint gdriver = DETECT, gmode, errorcode; int midx, midy; int radius = 100;

/* initialize graphics and local variables */ 5 o) ~# e& T+ T( v& einitgraph(&gdriver, &gmode, "");

/* read result of initialization */ 3 q2 \: `2 B' E$ i6 k* f* e) {errorcode = graphresult(); 2 E$ B! b5 x; ?7 F4 ~; Yif (errorcode != grOk) /* an error occurred */ ' ~$ c3 a! E& L- y" |{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 7 r4 a( j) X V E, ]getch(); 3 U h0 E1 c* a0 l& w, t0 u7 nexit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; ! I( N/ f& X$ c" I8 U& H# Wmidy = getmaxy() / 2; 9 y0 C/ f; ^* P# Msetcolor(getmaxcolor());

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

/* clean up */ * E8 k' N/ U# `% \0 P. agetch(); $ A' Z7 m- _4 o0 R; t! {closegraph(); $ J4 Z, [; l! s* m4 n/ o2 ? Vreturn 0; 9 Z, j7 h; P/ J: z) c} , z* p: w. _) M$ Y \

函数名: cleardevice 9 Z6 o# v( T% C' R9 L/ W8 @* G功 能: 清除图形屏幕 j$ O/ m: _6 A用 法: void far cleardevice(void); 程序例:

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#include 0 T: C' ?" N* W; f4 k3 Q7 m#include + i' O7 j* o4 |# Y4 | F; `#include #include

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int main(void) 2 J1 L( U3 u# G0 k4 {/ n{ /* request auto detection */ , z6 x, I8 t- R: s8 X( h; cint gdriver = DETECT, gmode, errorcode; int midx, midy;

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/* initialize graphics and local variables */ 9 W" B1 q! ~, Qinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ $ ~) J% B5 T X9 n" q+ ~errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ + v5 k4 e ?+ X3 d7 \. B{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); 0 f _+ @& b p2 Xprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 5 G" v6 i5 X! Z% W}

midx = getmaxx() / 2; . a1 ?' I8 |1 Y Fmidy = getmaxy() / 2; & t( l# ^" a7 x: \+ B9 Esetcolor(getmaxcolor());

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

/* output a message to the screen */ ; L& l) t, y# k+ iouttextxy(midx, midy, "press any key to clear the screen:");

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

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/* clear the screen */ . Z5 u v' h% [% Q, fcleardevice();

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

/* clean up */ ! ~% J: @! e: r# S, Y3 h2 D1 \getch(); closegraph(); Z- o0 Y8 A: b r1 breturn 0; } & T7 K& {! _" t0 {9 J & W5 g' ~' \) T9 l, ^: u

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函数名: clearerr 功 能: 复位错误标志 ^8 u2 ]8 j9 H: ~用 法:void clearerr(FILE *stream); 5 R0 s) |/ D- c程序例:

#include

int main(void) # l6 H7 N! D& @: R# q! Y% g/ g9 `4 S{ $ t8 G9 M( D, a) SFILE *fp; ! j; c5 d0 `3 n! A, B3 Ichar ch;

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

/* force an error condition by attempting to read */ ch = fgetc(fp); 7 `( @+ O+ a6 dprintf("%c\n",ch);

if (ferror(fp)) { /* display an error message */ : N; s9 e" c! Z7 _ Y7 d- Pprintf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ clearerr(fp); 8 D. w" V9 W! I! V0 M& p}

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fclose(fp); return 0; } 3 a7 z. [1 i! v. o& w 9 J0 m8 E3 @$ X, J3 H, s

函数名: clearviewport O! h7 D+ K5 ]' i' r功 能: 清除图形视区 用 法: void far clearviewport(void); 程序例:

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#include #include #include 5 u9 D# C2 ~ a4 J6 Z8 Z8 |#include

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

int main(void) 7 h! ]3 V0 A" B7 C/ l{ % C7 I, P& r( v; G/* request auto detection */ int gdriver = DETECT, gmode, errorcode; 1 D! m% E: J( H; ?- v( xint ht;

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

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/* read result of initialization */ $ O6 {8 u% N! l# h6 ferrorcode = graphresult(); " K- Q7 H) w. r+ j! ?; S( Bif (errorcode != grOk) /* an error occurred */ 6 X$ R d7 P( t" s& h' G: {9 E2 ~{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 2 ?2 j* P2 J0 xgetch(); exit(1); /* terminate with an error code */ }

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

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

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/* 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"); outtextxy(0, 2*ht, "Press any key to clear viewport:");

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

/* clear the viewport */ clearviewport();

/* output another message */ % E+ {8 K2 B( C [' g% T+ kouttextxy(0, 0, "Press any key to quit:");

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/* clean up */ 2 F T1 q9 E! Z/ e4 i! Egetch(); / ^0 R6 a/ z( g6 [closegraph(); return 0; 8 V& A7 Q# E8 M6 Q, @% i}

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函数名: _close, close 功 能: 关闭文件句柄 + J$ n- X7 J8 _! x, M9 c用 法: int close(int handle); % U+ _" _/ }7 T# v1 ~6 ?程序例:

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#include 6 U: f* s. u7 U& u1 j" j#include #include #include

main() { . V- z% H$ ?, X8 B( r+ ?5 jint handle; / Q% S) k8 {/ x" }char buf[11] = "0123456789";

/* create a file containing 10 bytes */ . b2 E2 B6 U" d, V8 ~# jhandle = open("NEW.FIL", O_CREAT); 1 {9 p' E A$ w0 ~& |3 Yif (handle > -1) % P+ j- b5 j& [( W{ " w0 o5 z/ u) M% b' Xwrite(handle, buf, strlen(buf));

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/* close the file */ : Q& P, l, J, b1 N9 {7 mclose(handle); - H! w' |; r6 h2 d} else 9 y# ?5 M) n# ^) O9 g{ : d: ~2 [+ N& ?1 U( cprintf("Error opening file\n"); 1 q$ m$ @5 ^* k- h$ l} return 0; }

函数名: clock 功 能: 确定处理器时间 ; O) `. C( Y. ?/ n& B a: F" g用 法: clock_t clock(void); 0 v2 j+ d! H# P) m7 L! m) A( D程序例:

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#include #include #include

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int main(void) { " E+ X9 Q. G( d8 Z3 Nclock_t start, end; 1 a$ h- a! m% C. h" astart = clock();

delay(2000);

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end = clock(); & v, Y( q& ?8 R' U- @( ^printf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; + A, W' z9 U% H. y4 k+ f. l} $ C( f; }3 I& c( b

函数名: closegraph - Y& i$ F. I! ?1 l功 能: 关闭图形系统 用 法: void far closegraph(void); & _/ Q v- \' y! t程序例:

#include 0 p4 P8 W) K3 {: e% W( w# z#include , }* N8 F. V8 g! T1 I5 ]: ]3 f- k#include ) p# H+ Z) c( Z3 {0 ?. ~#include

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int main(void) { /* request auto detection */ - ]( Y2 e" _& P) R+ @int gdriver = DETECT, gmode, errorcode; ! }# E9 F" D0 F$ A& `4 K' t% tint x, y;

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

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

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if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); : E+ ]* m- {3 K+ q2 G( _0 A; M( b2 Mexit(1); /* terminate with an error code */ 6 K: s/ A) ~7 K$ |4 y- d' U1 p3 v- P}

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

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/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); / x4 s E7 p, p; R5 \+ @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 */ $ x$ H, W9 P( \4 E+ L1 ?8 cclosegraph();

printf("We're now back in text mode.\n"); printf("Press any key to halt:"); $ Z$ x1 B2 j8 F6 n# U; l# y! `getch(); / N! q2 f0 X3 k" A$ Dreturn 0; . v6 D# a2 E: Y+ B0 v' D) N} 3 H8 y, K) V& {! v , m4 ]' U' T5 e' H, w8 F

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函数名: clreol 功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 0 _6 v$ _, V, C* Q& [, \4 K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"); cprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); 5 Y7 A& K, c& Z& A( Y# u- u& Kcprintf("Press any key to continue . . ."); gotoxy(14, 4); getch();

clreol(); ; v: }9 }& k2 ?" U3 Tgetch();

return 0; / X* X/ d/ I7 i: r. r. K0 b} 3 o- X2 p, q, V 5 O- U# I+ t/ M' `* M: {

函数名: clrscr 功 能: 清除文本模式窗口 ; E J( K h `& {1 S9 S用 法: void clrscr(void); 9 X! t' C9 F% ?* U4 A I4 V/ ]: Q程序例:

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#include

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int main(void) { int i;

clrscr(); ; U* G$ V$ R# h Zfor (i = 0; i < 20; i++) 0 A2 V- A, r& l2 l. k2 ^cprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); ! t7 X4 O9 i4 Z4 b% h" A4 Fgetch();

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clrscr(); cprintf("The screen has been cleared!"); 3 z. H1 b3 Z8 {% i; r- Fgetch();

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return 0; } * Z+ N2 s G3 C( }

函数名: coreleft 功 能: 返回未使用内存的大小 d G. {3 r' v: |: w用 法: unsigned coreleft(void); 程序例:

#include 8 t7 L, z2 Q ^: m#include

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int main(void) 3 I, h4 f& {% r! A/ i- ~4 e; V1 A2 f{ , `. P8 Z* g ?% h# {3 @7 Zprintf("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; ' @5 a0 k; V8 [ @& e} / d) t3 K* u8 I' @+ \

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函数名: cos 4 w" H6 B/ v9 F- o9 Y: q功 能: 余弦函数 . Q$ h4 k' ~ i r/ J6 v% j用 法: double cos(double x); 1 E! A3 H; }% p; R3 ]1 ^/ v8 I程序例:

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#include #include

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int main(void) : O7 S9 V% ]8 W/ {2 i{ ' Y( p9 Z( D/ T9 e. Odouble result; 5 m/ ~! ]+ m( |, C5 t: B* ldouble x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); return 0; } 0 V( K- v& R5 X7 `2 Q2 k7 U . N7 Y) Y$ ~0 ?6 o: _# ? B

函数名: cosh # `, D) F& b" f0 L J# y: M功 能: 双曲余弦函数 ; b8 D* W/ S( [用 法: dluble cosh(double x); 程序例:

#include #include

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int main(void) 1 G7 w5 m: Z4 @% f% K; m+ [{ double result; double x = 0.5;

result = cosh(x); ( W) k) P v( }3 ?! n9 f. Iprintf("The hyperboic cosine of %lf is %lf\n", x, result); $ N( I% Z* g/ M4 C4 Freturn 0; 2 h% R! [; c" p) H! e' ~} / J+ l4 A7 U8 m/ Z

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函数名: country + g, {/ W7 X& r5 x- X o* u功 能: 返回与国家有关的信息 ; _2 D) J# p% G, b2 n用 法: struct COUNTRY *country(int countrycode, struct country *country); ' L! X/ F* X m4 R程序例:

#include #include

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#define USA 0

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int main(void) ' ]* n; l6 w6 ^# F8 T3 A* O{ ) L* A7 h% D8 E, mstruct COUNTRY country_info;

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country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", country_info.co_curr); return 0; } 6 Z. a, [7 A& t# L. _+ Q* Z

函数名: cprintf ) {1 V; |9 f% V0 h! s功 能: 送格式化输出至屏幕 x% A/ z2 b: U5 Q3 d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 */ . a$ o" x' ?$ S, U F. J8 J0 c$ eclrscr();

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

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

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/* wait for a key */ ) y' d* ~9 m, x( J1 U4 Vgetch(); ( ?+ ]! I* K- n1 d+ areturn 0; 1 M/ N' C) h9 ~$ P+ ]} / G& t/ h6 E+ x5 ]( u: d7 C 2 o0 a, U! P* r9 [

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函数名: cputs / J* V1 N1 i1 w Z7 H. U7 x% z功 能: 写字符到屏幕 + O, {$ p4 h! `. m用 法: void cputs(const char *string); $ v) N/ R4 d+ d7 a程序例:

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#include

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int main(void) 1 D/ j: c9 C% J7 [1 {( o9 b6 S{ ) x# [5 C+ S7 V& z2 `/* clear the screen */ clrscr();

/* create a text window */ 4 N0 u" x0 W, C2 O4 I# Wwindow(10, 10, 80, 25);

/* output some text in the window */ , [/ S7 j8 @$ A. ]cputs("This is within the window\r\n");

/* wait for a key */ getch(); 4 F; P3 h- J& O! f6 c! h2 greturn 0; } ' K* g" |# a( H6 v 5 ]+ T. P9 A, i7 | ) ]. L1 w5 M) u# K, U

函数名: _creat creat - T" q& m6 w; r0 n- I' l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); # l6 Q. W4 {7 P# E! t6 B0 S程序例:

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#include #include ' b) D2 t# q, x& d2 R7 a3 [#include #include

int main(void) { int handle; . J5 W0 z, p) z! \( b: t' e8 Z& dchar buf[11] = "0123456789";

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/* change the default file mode from text to binary */ / T) `) ]# {# `2 R7 O) m_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));

/* close the file */ ) T8 D% |+ x9 ^close(handle); & p! z5 S: `6 `8 _) kreturn 0; x% p! W6 G/ {" {}

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函数名: creatnew - n$ O* x! [0 C# Y功 能: 创建一个新文件 s- |7 g; w9 y9 @- z+ J; `用 法: int creatnew(const char *filename, int attrib); 程序例:

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#include 9 N- E: w4 y3 g. X/ {2 n8 v#include #include R: X( z. o1 ?" w#include / a5 ?" h+ R# y, X) @% N! p, ]( E+ ]#include

int main(void) { $ t* T* o W* ]0 Fint handle; 2 q! D9 B# F: u- |( f$ Jchar buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ ' t9 V8 l7 B3 c! k- ehandle = creatnew("DUMMY.FIL", 0);

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if (handle == -1) 4 ^& d3 C0 V/ Z' Zprintf("DUMMY.FIL already exists.\n"); & h, q, i" |5 T; a+ Y5 @7 F9 G; ~else % y# `& t3 A. r9 c' @5 a m{ 0 G: O7 ]. N9 T3 Q' l' ]( Jprintf("DUMMY.FIL successfully created.\n"); / q+ k1 A& W0 d: o: s# G$ Ewrite(handle, buf, strlen(buf)); close(handle); T1 g& ^' E! |% _) r Y+ g$ h} return 0; , X+ |6 [ u: [8 t9 d! s7 J) q+ M} 0 S. G2 U }- N) Y 7 f; z$ z- m v$ M( B# f9 H ) s2 C8 Q3 C+ y& t- d+ o4 C9 {

函数名: creattemp 5 g( S( b! U0 Q' v0 \, k0 n7 z功 能: 创建一个新文件或重写一个已存在的文件 3 j7 U1 @/ ~2 P5 n4 j3 w用 法: int creattemp(const char *filename, int attrib); 7 p9 P) {! |+ K: K% j8 o2 V程序例:

#include #include #include

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int main(void) { int handle; char pathname[128];

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strcpy(pathname, "\\");

/* create a unique file in the root directory */ ' p8 l9 R, O3 @3 q+ hhandle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); close(handle); 8 V8 m) T( f8 H/ E7 Ireturn 0; } : J8 l1 t* b; n# |1 g

函数名: cscanf 功 能: 从控制台执行格式化输入 N' C! v4 Y+ x用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

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int main(void) . W8 [$ a- y; a+ c{ char string[80];

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/* clear the screen */ clrscr();

/* Prompt the user for input */ & i% O4 `( b- S2 a9 }1 k0 P3 jcprintf("Enter a string with no spaces:");

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/* read the input */ 1 E; y3 u2 g1 ?) R5 ^& Gcscanf("%s", string);

/* display what was read */ 6 t6 q. f+ M7 }' v& e# G. Ccprintf("\r\nThe string entered is: %s", string); e# U' A8 j* k; l9 K5 _return 0; ) m- c5 Y3 H7 B} + o& ` j( f9 G7 y

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函数名: ctime 功 能: 把日期和时间转换为字符串 用 法: char *ctime(const time_t *time); 程序例:

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#include $ j* V) F+ T$ c#include

int main(void) : ?4 J! @# P8 B* v* d{ + g) i. h& n4 d! P+ N6 x ktime_t t;

time(&t); / i& Y* \" C f9 h# u, e- ~2 Pprintf("Today's date and time: %s\n", ctime(&t)); 5 d3 S- q! I' s9 U6 W* w3 ]+ ireturn 0; 5 z: Y5 A9 I2 o E# Q" H A* b( B! U} 3 _1 u6 Z2 R( Q6 Z" R6 M 0 H0 m' V# o, h: G F7 h4 M

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函数名: ctrlbrk & `1 p4 e i3 }3 O- ?功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 1 t* ^; z0 ]3 ?3 z! w" A/ f程序例:

#include #include

#define ABORT 0

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int c_break(void) ' e6 b5 t: f3 L( |$ c7 S( u{ printf("Control-Break pressed. Program aborting ...\n"); return (ABORT); 4 V; ?" A2 P# k# @' ?( C# R" C* s% _}

int main(void) 2 Z' q B; A# b/ ~; @, M! C{ ctrlbrk(c_break); 3 q7 S+ d2 J( c2 v4 m- Y1 Qfor(;;) 9 Q& D& ?: H: }+ l6 v{ . g( s3 k& D: O+ u: s: oprintf("Looping... Press to quit:\n"); } return 0; }

hjl19890710hjl

特别感谢

gssdzc

还是感谢分享。。。

chenlk

有价值！

zjf

[em49]

谢谢啊

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