函数大全(c开头)

韩冰

函数大全(c开头) * ]5 W" E0 P2 g; \7 k( a# P

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函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 程序例:

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#include #include

int main(void) { % }5 l' p1 l9 E& L, Z8 B, Sstruct complex z; double val;

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z.x = 2.0; 9 Y2 v. U/ }3 B( U& |' x e7 Vz.y = 1.0; - [3 ]6 d/ b4 x6 A8 E' ]val = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); [2 k: @; h! L2 h2 {return 0; } 2 g! t+ J* e4 K& [! H& F/ ~' ^. _ / ?8 v4 M Q% K

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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); 1 B1 Z# g2 v5 T程序例:

#include 1 u% C) {0 r" q" e1 m. \( |#include

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int main(void) . ]2 r' _2 ?1 d6 J{ char *str = NULL;

/* allocate memory for string */ ; a0 @' i& H: X6 H. B! u* N4 vstr = calloc(10, sizeof(char));

/* copy "Hello" into string */ 1 b& M+ ~/ z. _1 M9 `7 Y' ostrcpy(str, "Hello");

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

/* free memory */ 3 w2 R& @+ O8 C( Z$ c, l! E8 Sfree(str);

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return 0; } ) _9 ~$ H4 U# O5 A a, H R+ ]* a# [/ X

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函数名: ceil 功 能: 向上舍入 # v3 \7 P4 G$ x$ W- j. @/ J用 法: double ceil(double x); 5 y5 x1 d3 N) l程序例:

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#include #include

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int main(void) / {* P: q; S* l I; V{ - @. {5 @, O. L8 `- h. @, s0 mdouble 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); + z0 E6 r/ W7 M- L9 qprintf("number rounded up %5.2lf\n", up);

return 0; 3 m N. S, ]+ W} ( h0 H7 b" D Y, [5 J4 ^

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函数名: cgets 功 能: 从控制台读字符串 # a9 {5 d. S; i7 U用 法: char *cgets(char *str); 程序例:

#include #include

int main(void) { + b: n( V1 ~# Y) I4 J8 achar buffer[83]; \1 ^( Y+ M" K0 uchar *p;

/* There's space for 80 characters plus the NULL terminator */ & K* ^% k9 H/ \5 v: q- q/ `buffer[0] = 81;

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printf("Input some chars:"); 0 J9 a& Q# [8 p! u- \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);

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/* Leave room for 5 characters plus the NULL terminator */ # ]1 d' @% q9 @ y5 }buffer[0] = 6;

printf("Input some chars:"); / g4 d$ d& i( H, d% `* |3 ip = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 6 W. a+ U6 O6 Tprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); 3 N3 r, B) }, H7 V; E$ z Ureturn 0; } 9 U5 w+ @; P3 ~" K / R/ c# r+ x n

函数名: chdir 功 能: 改变工作目录 $ v$ m+ ~* b$ E' H& W4 Z用 法: int chdir(const char *path); ( _3 N! R% P/ s4 ~# P9 K5 _/ M程序例:

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#include ) p# L8 q1 p L#include ]6 K3 z( P* x5 l#include

char old_dir[MAXDIR]; + R' G6 @" ^9 f9 l3 A `: e T% tchar new_dir[MAXDIR];

int main(void) 2 Z3 X0 o: H |* y{ if (getcurdir(0, old_dir)) { ' w! g& l, x. r" ?/ Z xperror("getcurdir()"); 2 t* J8 P1 W p4 Uexit(1); } 0 ~ ?! [4 Q. |- S) A% Sprintf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) 1 p8 F% S# y F+ T }5 j{ perror("chdir()"); exit(1); 3 ?1 B5 P* ] c' |4 n* P" m}

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if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); 5 v8 U8 Q) Y) z) p4 O4 r} printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); + ~0 W+ S/ v( x* t) v' y$ r6 \if (chdir(old_dir)) { perror("chdir()"); 4 u) L$ t j' U! W- N |# X. b/ {exit(1); }

return 0; % s7 d( D7 P1 A; u9 ?' J- G} # c* c+ h6 Z( Z/ Z1 d- _

函数名: _chmod, chmod 4 G, g! |0 l9 |功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); " ^; t; M. ~5 J程序例:

#include 2 l# X0 F8 E/ N5 m9 I#include 7 F! N4 N, ^4 L2 O9 c& h#include

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void make_read_only(char *filename);

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int main(void) { make_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); 6 l# @! Y8 w2 F0 W/ u+ e: _return 0; }

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void make_read_only(char *filename) { int stat;

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stat = chmod(filename, S_IREAD); if (stat) printf("Couldn't make %s read-only\n", filename); else $ \! s6 y8 z" J$ Jprintf("Made %s read-only\n", filename); } M3 X+ b, _/ ~% v6 `

函数名: chsize * X$ j6 G8 O+ v7 J- G/ B3 E9 b) z功 能: 改变文件大小 用 法: int chsize(int handle, long size); ! r6 ~2 x% @. C1 s程序例:

#include #include $ k( n: j" s& P' t; P% D" g( K#include

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int main(void) . p, b& \9 u% S u! L( G{ ' s0 A/ g2 q& o* O( J, Xint handle; 7 j. O% e7 C, Z( nchar buf[11] = "0123456789";

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

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/* truncate the file to 5 bytes in size */ 6 d, A% j9 P9 V1 f# ~1 gchsize(handle, 5);

/* close the file */ 3 f8 M5 B# D/ n: L3 jclose(handle); return 0; 6 X6 C; f* e; C) L5 u} ) ^9 V/ [) U6 ?$ {- G c2 c6 r4 f- g

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函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 ( ]0 G( X. c0 J* s* f* ~' l用 法: void far circle(int x, int y, int radius); 程序例:

#include #include ! V2 b/ s" ]- K#include * N/ U6 R" Z$ _: q5 g: ?: c7 @4 `. G#include

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int main(void) { 1 t9 V3 J6 C! @6 v2 i( M& ^/* request auto detection */ int gdriver = DETECT, gmode, errorcode; - ]% Q) F8 ^; ?5 lint midx, midy; int radius = 100;

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

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/* read result of initialization */ / [. m2 b1 W) h" |( K6 w, }. Derrorcode = graphresult(); * @3 X7 L& F) w7 @7 uif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); + G4 y0 p0 `& F0 Y: Qexit(1); /* terminate with an error code */ }

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

/* draw the circle */ , l/ C( x# a- C) x/ Ocircle(midx, midy, radius);

/* clean up */ " v w; m6 @- i' F+ N5 Y" ugetch(); " \5 q5 m/ X4 C& @; z4 kclosegraph(); + f+ k( ~ ]5 ?7 [' ereturn 0; 0 P3 S+ N: N" C, A- F- h} % t5 s; X$ M- T, b2 J+ o

函数名: cleardevice 功 能: 清除图形屏幕 , ~. }& c$ A9 l用 法: void far cleardevice(void); 程序例:

#include #include & ]/ {. [' S! ~# _) ^#include #include

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int main(void) { /* request auto detection */ : H# N) Y; ~5 I/ ]: c% C* x* ?int gdriver = DETECT, gmode, errorcode; ! T9 v' s! K, | G, jint midx, midy;

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/* initialize graphics and local variables */ & s9 \8 n0 o: q* Y5 Q5 Q! t4 Iinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ 2 \8 V5 H) f% M" ~. G' perrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ) m# o0 v4 m# R: [, |; F{ ' m. K i. O4 w" y3 o: lprintf("Graphics error: %s\n", grapherrormsg(errorcode)); / N* @# g4 j6 Y1 {/ wprintf("Press any key to halt:"); getch(); & Y5 m; h m {8 I: E% ^1 L/ t- N9 @exit(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 */ : y8 J6 l* |6 z6 B3 z6 l8 `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();

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/* clear the screen */ 7 |/ ^# ?0 `+ Ucleardevice();

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/* output another message */ " b% s/ T$ T) z0 n. Qouttextxy(midx, midy, "press any key to quit:");

/* clean up */ ; \9 ?# K. u5 m8 c5 j* ?1 S( ngetch(); closegraph(); return 0; } 8 s6 B9 W8 [$ u4 } 7 g& P( V2 \! F" ^9 f

函数名: clearerr ( h) a; d$ w$ R+ \: \% E功 能: 复位错误标志 $ ]- ~0 x0 Y Z4 b" v用 法:void clearerr(FILE *stream); 程序例:

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#include

int main(void) . u5 N7 d p9 ^+ O$ O3 ?" y5 Y{ ! O# K) x" u, \FILE *fp; char ch;

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

/* force an error condition by attempting to read */ 8 E ?9 J4 v. lch = fgetc(fp); printf("%c\n",ch);

if (ferror(fp)) + v, W5 {! t3 `' q$ W! r. B# i{ /* display an error message */ E. b4 x( S; b5 lprintf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ ' U4 T$ u' I0 X% I! o- s4 wclearerr(fp); }

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fclose(fp); 6 j+ D7 ]& @ c5 n) ` ?return 0; } 9 v3 U8 r" r9 k' G$ J; ~, }/ ]

函数名: clearviewport 功 能: 清除图形视区 用 法: void far clearviewport(void); 程序例:

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#include 4 c# J+ z8 b4 P! _#include 2 ]' o9 l$ {% ^% N" L#include #include

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

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int main(void) $ t: I. [3 B2 m& W+ s- U. H" q2 U{ , C0 A( C+ i( w2 p" K/* request auto detection */ 2 y% j4 L @4 |int gdriver = DETECT, gmode, errorcode; int ht;

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/* initialize graphics and local variables */ : h9 m! Q6 F1 r2 z5 ainitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult(); 3 x4 u b" @, v' G% ~* B2 Uif (errorcode != grOk) /* an error occurred */ ; ?# ~/ Z% m0 v/ z; {# V% Z6 s% y{ - U% }" y+ _. M7 \& Wprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

setcolor(getmaxcolor()); 4 b( D7 {5 M! U! J6 tht = textheight("W");

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/* message in default full-screen viewport */ " S# I* O- H$ y( ]* Aouttextxy(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 */ ( B' y8 q* G& p: Couttextxy(0, 0, "* <-- (0, 0) in smaller viewport"); outtextxy(0, 2*ht, "Press any key to clear viewport:");

/* wait for a key */ 9 i) B9 M$ v+ ^getch();

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/* clear the viewport */ clearviewport();

/* output another message */ / E. Z2 M, O5 n9 }- ^: j) n( J# Kouttextxy(0, 0, "Press any key to quit:");

/* clean up */ % D' |! _9 I, Q* c0 \+ d5 q1 n. B+ Z% ]getch(); 3 f- m# K; D' K8 t) k( Lclosegraph(); return 0; ) F9 g2 p0 r5 G( s( D5 ?} + q- r& @4 m! Y* g# j* E5 l+ Q# v ! z. Z1 o1 F1 _: S E, Z. D1 s

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函数名: _close, close 功 能: 关闭文件句柄 用 法: int close(int handle); 程序例:

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#include #include #include #include

main() { ! u0 v8 ?7 X; g6 qint handle; char buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); 0 g X8 C9 v' C4 N9 O6 S( mif (handle > -1) { ; W9 U' T: f5 U# S/ ^' i0 Z8 Ywrite(handle, buf, strlen(buf));

/* close the file */ 4 v% z) w1 _! C) r7 q" Pclose(handle); } else 4 n Q4 i! {' ]7 Z{ printf("Error opening file\n"); } return 0; } . j3 ?+ l& p& |( b' d/ K# |

函数名: clock 功 能: 确定处理器时间 ; q" J$ e4 K/ `4 J用 法: clock_t clock(void); , ]9 M7 q0 @( b* j程序例:

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#include ' V/ k+ |+ z+ l, O# D% ? G. d#include #include

int main(void) W: z4 g/ V$ q{ + k0 m0 g! G% L0 K! k. bclock_t start, end; 0 Y3 ?4 |4 {: A, W6 P; r8 tstart = clock();

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delay(2000);

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

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return 0; } 0 |# j; V5 t& O* Q / x. P& c$ }2 F' t: F0 C

函数名: closegraph 功 能: 关闭图形系统 用 法: void far closegraph(void); 程序例:

#include #include #include #include

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int main(void) { /* request auto detection */ " }/ z# J% ^& ?. z/ _6 }% Oint gdriver = DETECT, gmode, errorcode; int x, y;

/* initialize graphics mode */ ~2 S$ T' l! ainitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ * M F5 ]1 J5 {* A, terrorcode = graphresult();

if (errorcode != grOk) /* an error occurred */ ' q1 r9 E! R7 X5 y{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); ' _! K; D# Z" Y6 ]' x/ ?printf("Press any key to halt:"); ) k: x2 }: s* K2 j) i8 X9 Dgetch(); + h* m ~, }& Q& X' I: b9 d3 Hexit(1); /* terminate with an error code */ $ f; J7 C" G6 F/ b}

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

/* output a message */ 8 w. K" F* D( I3 h" ysettextjustify(CENTER_TEXT, CENTER_TEXT); ' H# a2 y) I; L/ _+ K, @* _5 b9 u0 fouttextxy(x, y, "Press a key to close the graphics system:");

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

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/* closes down the graphics system */ + O. D6 ]7 V" L/ ^closegraph();

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printf("We're now back in text mode.\n"); - e# o+ |9 n- a zprintf("Press any key to halt:"); getch(); " {9 s6 ?! g$ M, Yreturn 0; } : ]' Z! `3 O# @1 P+ F " E/ g: _. U) P% \! | , h4 q, D; q% T3 @

函数名: clreol 功 能: 在文本窗口中清除字符到行末 6 p2 e" a4 y( D" `用 法: void clreol(void); , ?* D. Q6 I6 ?' Q* z( [7 ^/ N程序例:

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#include

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int main(void)

{ x K' A6 a) b8 p4 h- ]clrscr(); % \( V' A, C; m% kcprintf("The function CLREOL clears all characters from the\r\n"); ) v% ]9 O3 h1 a' rcprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); cprintf("Press any key to continue . . ."); gotoxy(14, 4); y) n+ j. ?# F h) f2 J# Cgetch();

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clreol(); getch();

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return 0; } - B: g# i& Y! I8 `$ @$ g D/ ?& q ! K0 ?/ S7 Z& O4 ?# Y" g8 d

函数名: clrscr 8 \/ ]8 c% R0 r+ i4 h功 能: 清除文本模式窗口 1 o/ M7 I" a" _7 |. s1 V用 法: void clrscr(void); ' N ]& J" p# J" @7 T; e程序例:

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#include

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int main(void) " A3 f, K- X* d9 k% G1 K{ int i;

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clrscr(); - e1 ~# h" a wfor (i = 0; i < 20; i++) : R0 Q8 M) _# I* O% Y! e' Vcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); 0 ~4 \/ }) ^$ `+ egetch();

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clrscr(); 4 S7 F5 @& w/ u$ ]+ {4 n6 A9 Q, V! Ucprintf("The screen has been cleared!"); 8 f/ s. R$ d3 u3 Agetch();

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return 0; }

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函数名: coreleft 功 能: 返回未使用内存的大小 7 U1 }1 O6 B3 s% ?. B' d用 法: unsigned coreleft(void); 7 o. r4 B4 t& H& E程序例:

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#include #include

int main(void) . d# Z1 [3 ` B6 M$ o{ printf("The difference between the highest allocated block and\n"); 2 w2 C1 s* B3 w' Y, L6 Q6 Zprintf("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 功 能: 余弦函数 用 法: double cos(double x); . ?* A% b% {# a* ^# I程序例:

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#include #include

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int main(void) , z3 k; @/ R2 g3 f7 k{ $ N( U& f# q6 O- g: n$ u, zdouble result; double x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); 5 N+ f6 u8 R2 w% F/ X6 U$ Nreturn 0; 1 k% t3 K* L3 x4 `}

函数名: cosh 功 能: 双曲余弦函数 2 ?- N6 z! l. a1 w2 d1 E7 ?3 K% N; {- o用 法: dluble cosh(double x); 程序例:

#include #include

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int main(void) + d! f9 [( G# S( N5 k{ 3 }" r+ K5 r+ w( H8 |# }$ F( j2 t% idouble result; ) Q/ \% Z! ~! j! o6 w# g* E4 v) Udouble x = 0.5;

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result = cosh(x); 5 E" G; o9 n& Wprintf("The hyperboic cosine of %lf is %lf\n", x, result); ~/ B1 r) a7 ?return 0; 3 @% J8 [( {; W1 T3 T} # l- o. I. `0 N* c, Z8 |1 L

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函数名: country 6 N% n2 S [8 E* C6 B( _功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); + ?8 [8 }7 O8 x' l) A0 x, [) _" j程序例:

#include #include

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#define USA 0

int main(void) { ) {' a1 v( R0 u% w# p' q* S6 astruct 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; D0 J; a) Z+ a* {} . M+ z! b6 q* ~- ^$ K2 g7 z- u' u % v2 D+ s# H3 @# M3 ^* z, E & D3 X4 {0 N8 \, k1 Y

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函数名: cprintf * C a9 m9 e( `6 f+ j, {, [. y' f功 能: 送格式化输出至屏幕 & x( ?! n. O6 ?- ?6 G& D3 X用 法: int cprintf(const char *format[, argument, ...]); 程序例:

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#include

int main(void) 8 Q7 e, p4 j# ^5 T{ /* clear the screen */ clrscr();

/* create a text window */ ' \5 F. y3 j3 ?' I* x) t0 ]& Bwindow(10, 10, 80, 25);

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

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/* wait for a key */ & X6 r4 Z+ x8 o: M. agetch(); return 0; 5 d9 ] v9 e/ C& F4 T* g}

函数名: cputs 8 j) s, s5 O* S! K) ]+ N功 能: 写字符到屏幕 - s+ x H5 b: @% o1 v8 \+ R用 法: void cputs(const char *string); 0 F8 h3 Q3 n0 ?, u$ ?4 e7 F程序例:

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#include

int main(void) " h& W% d+ T3 M @{ /* clear the screen */ 1 k+ G6 Y/ ?* n- Hclrscr();

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

/* output some text in the window */ ! y# V0 ^. N" P1 G4 H; ocputs("This is within the window\r\n");

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/* wait for a key */ getch(); return 0; } ! l" Z: `+ ^* u7 h

函数名: _creat creat 1 h. k* T) z7 G# U7 X. ?功 能: 创建一个新文件或重写一个已存在的文件 3 l# M) h* k& G. d用 法: int creat (const char *filename, int permiss); 程序例:

#include #include - C7 T5 r' U) d @6 J( H+ Q6 T6 P1 d ?/ Y#include 1 d/ B7 D5 f3 A2 f8 a1 F/ O#include

int main(void) ; n, |2 r8 D* \7 b+ W8 t{ int handle; 1 D. m+ N' c0 B; r rchar buf[11] = "0123456789";

/* change the default file mode from text to binary */ % a0 M! m9 [' ~$ @( d2 {_fmode = O_BINARY;

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

/* write 10 bytes to the file */ }* _/ l% H6 a& Q* _5 Qwrite(handle, buf, strlen(buf));

/* close the file */ 4 E( S* X+ f# _9 {" F* iclose(handle); return 0; * O$ O& H0 b a- a) _2 b} ) T! e/ j& w8 }0 {4 d( d% I" N

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函数名: creatnew 功 能: 创建一个新文件 用 法: int creatnew(const char *filename, int attrib); " C$ A9 w7 A( \' b程序例:

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#include #include #include #include 5 ?" a8 e+ e9 k8 l1 L3 y#include

int main(void) { # g' F% S6 x% ]0 }int handle; char buf[11] = "0123456789";

/* attempt to create a file that doesn't already exist */ ) {: @! B% D4 J# `handle = creatnew("DUMMY.FIL", 0);

if (handle == -1) D8 L0 }4 f* ^4 N8 ~0 h3 Tprintf("DUMMY.FIL already exists.\n"); else { printf("DUMMY.FIL successfully created.\n"); $ U; P* Q3 i8 z! y& _' _$ Iwrite(handle, buf, strlen(buf)); . r$ j$ n3 d- ?1 |4 q# b0 `8 bclose(handle); } 1 ]( V G) K8 [return 0; } 0 E- \3 c3 M' C% e* v9 o% O1 G

函数名: creattemp $ q1 C9 e! t6 [% p) C! e+ B0 \7 W; ?功 能: 创建一个新文件或重写一个已存在的文件 # P( z @5 g* l用 法: int creattemp(const char *filename, int attrib); 程序例:

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#include # E5 X( X/ F) l q2 m8 C& w3 Q#include 8 c4 M+ Q p! P2 s. A3 R#include

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int main(void) { int handle; 9 `" ~% o. d; Jchar pathname[128];

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strcpy(pathname, "\\");

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/* create a unique file in the root directory */ 3 c+ q3 ]* ?/ e; x0 W# w* Y) o3 khandle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); 3 z' @6 Y# d4 P. R3 k9 U0 C' n. qclose(handle); / |! X% ^7 u+ s; Lreturn 0; . e7 K) _% w' L7 x} : Z& N" b- h+ ]0 w" ^

函数名: cscanf 功 能: 从控制台执行格式化输入 7 G7 F, g, v! Y用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

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int main(void) { 5 l T2 [2 ^3 s0 [! x# l6 |% U) q+ Rchar string[80];

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/* clear the screen */ clrscr();

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/* Prompt the user for input */ ' O6 Y# R/ O( v, k4 Z7 i' fcprintf("Enter a string with no spaces:");

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

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/* display what was read */ 9 h4 h, B1 Z! |+ wcprintf("\r\nThe string entered is: %s", string); return 0; ( D8 X3 q" F- Z; Z* C3 g+ ^} ; p' Z0 H. a9 ?- v: p 4 {/ l Z* _! ]3 o

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 . ^1 T0 J( V: L#include

int main(void) { + N& L9 @! E- Ktime_t t;

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time(&t); printf("Today's date and time: %s\n", ctime(&t)); return 0; } * P O( X9 E( T( V% Q6 A$ b6 m ( f$ L) B# }% N6 e- U. K3 x* v

函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 程序例:

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#include : G! `& V+ O: T& `+ c9 P#include

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#define ABORT 0

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int c_break(void) 7 h, e* m6 p, K9 K+ P{ 0 k+ l# z: v* i- \% F B6 Oprintf("Control-Break pressed. Program aborting ...\n"); * k3 u5 T9 I1 I6 breturn (ABORT); 6 M! I& }0 O* v& U}

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int main(void) 0 a) K' E" |( d j{ ctrlbrk(c_break); for(;;) { 1 w" y0 j& b+ U/ x( R: Z8 F5 F: vprintf("Looping... Press to quit:\n"); 4 X4 F5 e: c1 I/ L7 R2 Y} ) z. U- C9 q; C: C, W, greturn 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