函数大全(c开头)

韩冰

函数大全(c开头)

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函数名: cabs 9 ?) Z0 m j! E8 d( {0 @" I" r2 e功 能: 计算复数的绝对值 / P4 r8 B) H! y9 U9 j用 法: double cabs(struct complex z); 程序例:

#include #include

int main(void) . ~. [4 \. `* c" V1 a! A! S5 n{ struct complex z; double val;

z.x = 2.0; % L3 b3 R0 f2 E+ W8 |" Dz.y = 1.0; val = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; ) g& @% `4 g& W7 j; ^} 2 p( W: E, P1 D2 T1 k 8 W7 e3 D" T' d

函数名: calloc 功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); / f. k: m1 E. v2 d; d4 Q程序例:

#include #include

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int main(void) { 5 I$ A+ S/ d$ zchar *str = NULL;

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/* allocate memory for string */ # Z/ x" S! W5 p, T# J+ @9 O9 pstr = calloc(10, sizeof(char));

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

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/* display string */ * Y( U% E+ Z- ?9 ^( m mprintf("String is %s\n", str);

/* free memory */ ' ~4 `1 O2 l, }; H/ efree(str);

return 0; } % b8 D& E( T3 q ^. W" r2 d3 M, l 8 r& J4 i, r. ?$ [+ K6 r l! t

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函数名: ceil 6 A4 j( l) d! y功 能: 向上舍入 用 法: double ceil(double x); 5 {3 M* V- j0 x# y* R+ V7 y程序例:

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#include #include

int main(void) { double number = 123.54; 4 ?+ @- y5 W/ n- i G; m& X! Bdouble down, up;

down = floor(number); + A3 u/ k L4 ^# Lup = ceil(number);

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printf("original number %5.2lf\n", number); 1 W' Y# U) H! s+ ~8 Pprintf("number rounded down %5.2lf\n", down); - G3 J6 `( ]4 P# [printf("number rounded up %5.2lf\n", up);

return 0; ' t* i* R, Y7 \/ f0 z/ ?} - y, q; }4 z4 ?0 K1 a* l2 Z ) a# `" l. _2 ~9 s & R8 k1 L& z& @3 A2 x, Q" N

函数名: cgets , O: i0 O: y2 ^" Y/ _! z* _功 能: 从控制台读字符串 用 法: char *cgets(char *str); . v& S" C- [( a9 }程序例:

#include #include

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int main(void) { 0 \' H5 S' f. g2 Uchar buffer[83]; char *p;

/* There's space for 80 characters plus the NULL terminator */ 5 N5 w. g' H) K. s; C4 h2 }! _buffer[0] = 81;

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printf("Input some chars:"); & b2 h; w! @) m1 Q5 x4 n# y9 q: ap = 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 */ ; m5 P/ B( Z* X( q$ G8 U; S5 J" Jbuffer[0] = 6;

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printf("Input some chars:"); p = cgets(buffer); {) t2 L2 N3 z: |- G( y% ?printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; } & N- S5 M/ R# E

函数名: chdir 功 能: 改变工作目录 0 M" ]4 i, \( [+ L& f8 J用 法: int chdir(const char *path); ' T* {! m+ t% @6 m7 b, E+ Y4 y程序例:

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#include 7 m! K; T$ k( t# H5 B" x#include ! Q, |2 @0 |; w9 C5 Y#include

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

int main(void) { / H, \) Z' o5 @2 M- }, sif (getcurdir(0, old_dir)) { 5 o0 H i2 V) Eperror("getcurdir()"); ) r; \6 u4 X& V6 o" I: Fexit(1); # r8 y- O+ @8 t& R% p} ; A3 d( Y4 ^9 r2 V4 Zprintf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) { perror("chdir()"); exit(1); 6 \9 p- F. G0 m9 l( s% ]- R. b}

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if (getcurdir(0, new_dir)) { ; V5 e0 c9 T% Nperror("getcurdir()"); # p* L- Q1 N. Z% C' P) Iexit(1); } ) d1 `( n- m: \; xprintf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); , _2 f% \3 E) S) Lif (chdir(old_dir)) { - Y7 d; }8 Y _4 cperror("chdir()"); exit(1); }

return 0; } # T, u. B) o9 H# _. |0 f7 d

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

#include #include #include

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void make_read_only(char *filename);

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int main(void) { make_read_only("NOTEXIST.FIL"); - e2 y) \. O' \3 j! s8 ~, Bmake_read_only("MYFILE.FIL"); return 0; 8 @& W; c% [4 B8 l}

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void make_read_only(char *filename) { $ T7 g5 X o/ V# q8 Dint stat;

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stat = chmod(filename, S_IREAD); if (stat) printf("Couldn't make %s read-only\n", filename); ( F7 d/ |; I9 u L3 } yelse printf("Made %s read-only\n", filename); } J/ }/ J( ~! A3 K: x% O l # _5 w4 W( S! K& l

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函数名: chsize : C9 K5 t' L* D7 x# N功 能: 改变文件大小 / E: k+ k, G/ d' j8 R用 法: int chsize(int handle, long size); , i# h/ r" s: D) i3 d% [程序例:

#include 8 U- y; w" j0 l; S: O#include % N% h' K0 A. G. r8 y#include

int main(void) # G/ i! o+ G6 e: o{ int handle; 1 }+ P( k E- J! j1 q; X. kchar buf[11] = "0123456789";

/* create text file containing 10 bytes */ handle = open("DUMMY.FIL", O_CREAT); 1 G4 c' y6 n) Y1 Z5 Lwrite(handle, buf, strlen(buf));

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

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/* close the file */ close(handle); return 0; 9 T. K8 Y% g: v0 I} 6 Y5 q/ k0 y3 K' l) v

函数名: circle ( i! \! n0 @4 a: }$ q g m- [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 9 e+ ^6 i9 N$ b9 x#include #include 0 p5 o: [9 ~9 m7 Z' j. ?#include

int main(void) 1 g" {% t: o$ ?# G# q9 [+ W{ /* request auto detection */ 1 c, W- J/ v' H& @. S' oint gdriver = DETECT, gmode, errorcode; int midx, midy; int radius = 100;

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/* initialize graphics and local variables */ z2 P: j6 ~( A2 |: U# x0 Z# H( `0 jinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ 3 |9 P: j! a; X5 Oerrorcode = graphresult(); 9 R0 Z$ W1 W1 Z6 V) X V. cif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); ! N- P0 t% T; j7 ]" Q" A* E: Ugetch(); exit(1); /* terminate with an error code */ % [$ J1 s5 c' F}

midx = getmaxx() / 2; 6 X6 k1 |5 D! a9 ~/ xmidy = getmaxy() / 2; setcolor(getmaxcolor());

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

/* clean up */ getch(); closegraph(); % P" \) A! V! Preturn 0; } & e: J: `3 ]5 q) T5 p, t

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函数名: cleardevice 功 能: 清除图形屏幕 用 法: void far cleardevice(void); 程序例:

#include 2 B8 E: t2 N% e' g# ~% R#include #include ' V! @0 @1 [' k: J# W9 o#include

int main(void) 5 V- X! [$ l, q8 C- V7 O{ 1 I; {8 }8 |+ S& d/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy;

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

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/* read result of initialization */ 1 D$ e# N7 O/ berrorcode = graphresult(); * [9 V' {$ F. C! j0 p7 ^6 E9 ?if (errorcode != grOk) /* an error occurred */ 7 I# Y( T! @5 ~' S{ ~' A# D- {# k6 wprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); % I) u' h" _# K) D3 Wexit(1); /* terminate with an error code */ 2 _- E) G- L' q: f4 v, P1 m}

midx = getmaxx() / 2; midy = getmaxy() / 2; % z, w+ z7 M& q* usetcolor(getmaxcolor());

/* for centering screen messages */ ! {% Y! a+ i \, Fsettextjustify(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 */ cleardevice();

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/* output another message */ 1 C# i# n) S) i6 Vouttextxy(midx, midy, "press any key to quit:");

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/* clean up */ & |2 C$ H. A* l2 d" \; ], \getch(); closegraph(); return 0; 3 O) Y, C6 ?; v) R} & z$ |) { X# w( A9 l + s- E! D1 J7 G- v# R* P, W7 C

函数名: clearerr 5 D1 M) n% y/ N$ W- B) z功 能: 复位错误标志 g0 c) `2 A5 I: j5 U# i O用 法:void clearerr(FILE *stream); 9 p8 z9 e0 u* }4 b( N- W2 }程序例:

#include

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int main(void) { FILE *fp; : {. a( [' z- R+ z- L+ Gchar ch;

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

/* force an error condition by attempting to read */ ) h& q1 s& Y: f& u# C0 Y1 vch = fgetc(fp); 8 V' d# u9 }) z) m0 U8 R; Wprintf("%c\n",ch);

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if (ferror(fp)) { /* display an error message */ printf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ clearerr(fp); }

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fclose(fp); ; s, T6 J) C% e+ T! e% {return 0; ; E9 U' F4 i6 ?/ T} + X/ m7 K" {' Y$ U/ j. U: y 1 U6 l+ S; p- Z1 r4 O- a

函数名: clearviewport 功 能: 清除图形视区 $ p5 M! E9 V* _! D1 b' ]用 法: void far clearviewport(void); 程序例:

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#include #include % n$ }# A& x F4 H1 r5 g, l#include #include

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

int main(void) * d3 f" I: h3 [3 w; x- o2 }{ 6 g9 R" h7 b1 e2 J; V3 v, g/* request auto detection */ 1 x- ^2 s& k" ?- R. w9 jint gdriver = DETECT, gmode, errorcode; : O9 e1 r/ S, j6 [1 k- `int ht;

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

/* read result of initialization */ 1 F5 c5 b* a" ~/ d: kerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ : k7 X* F, k0 R% T' w, Y; c{ / @ Z& x b" e5 e9 \) g8 l5 Aprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); 3 m$ Y& _' C, t+ T$ C# |# D% @exit(1); /* terminate with an error code */ % ?. A* u: B8 `# x}

setcolor(getmaxcolor()); # j+ E: e4 _" y6 g& T/ }) A9 Lht = textheight("W");

/* 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);

/* display some messages */ & S/ z$ G/ K( O) a% |' Xouttextxy(0, 0, "* <-- (0, 0) in smaller viewport"); , h7 K; ^( T0 i. uouttextxy(0, 2*ht, "Press any key to clear viewport:");

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/* wait for a key */ 4 n' S+ A8 z1 d8 ggetch();

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/* clear the viewport */ clearviewport();

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

/* clean up */ - @6 {5 N- W/ i: Y' e( ^getch(); closegraph(); ' w0 y+ q& \- E, J) Jreturn 0; ( q1 J( p8 Z. c$ v% ]' c- M: y} ; \# \0 |. Q6 Y! F+ F 5 r2 Y/ o! X, I$ Z* g5 Q7 ^- B

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函数名: _close, close . \$ t! e* d' f5 D' ]( Q功 能: 关闭文件句柄 , e5 E8 p; m' H7 K4 X8 ~6 t+ @) P/ X用 法: int close(int handle); 程序例:

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#include 3 X& C- `8 U% O; v) Z- n#include ! |# u7 P* B5 z! e#include $ j) {+ K- U$ q: d, u7 `#include

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main() { int handle; # v9 A, H8 m x0 r8 achar buf[11] = "0123456789";

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/* create a file containing 10 bytes */ + o! Q1 k8 v% q9 u8 C2 Jhandle = open("NEW.FIL", O_CREAT); if (handle > -1) { $ D- k$ r: X' x1 ~6 \' R- jwrite(handle, buf, strlen(buf));

/* close the file */ , [/ S7 |8 _4 Y8 m" A# Nclose(handle); 1 o4 `5 t, \' O ], ?5 w} 1 m+ p% u5 j2 t; t5 f2 Selse & F" {/ a ^. k- g3 r{ printf("Error opening file\n"); } return 0; 8 k( d9 S5 D# {: I% p} : z; b7 e5 ]& A/ h

函数名: clock + ]3 V' G' s% S: L" T: _& K2 ^功 能: 确定处理器时间 & O$ @- G" P% T用 法: clock_t clock(void); 程序例:

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#include 9 z% ^3 B% A& J* z8 p. ]#include #include

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int main(void) { * c. L/ Y! d5 W0 qclock_t start, end; start = clock();

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delay(2000);

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

return 0; } & Q1 D* [: A+ x1 a# T3 I # Y7 q% g5 w) Z8 l; O6 e

函数名: closegraph : ]3 U& Y: r; W8 V$ V功 能: 关闭图形系统 用 法: void far closegraph(void); 程序例:

#include ( L3 G; o& N( G/ ?( R( d/ _#include ' |; V8 D' \9 o#include 3 i& V9 I% ^3 d$ n#include

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int main(void) / s3 T' }. x: W7 f3 A0 A{ " i8 |/ y: g3 c/* request auto detection */ & o9 t3 Y+ O- a; C3 ?$ i, v$ Eint gdriver = DETECT, gmode, errorcode; * p3 A' n# l* U" W% pint x, y;

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

/* read result of initialization */ Y+ J# b4 D: Y. l2 h- E& Y8 `& @errorcode = graphresult();

if (errorcode != grOk) /* an error + S2 l6 X2 i6 e6 b9 V6 p6 Zoccurred */ . h9 f; k+ {: Y- c$ k# u. g{ ) {, H5 y- x; d, C# Nprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); , Q0 i( ~8 v- u, }4 xexit(1); /* terminate with an error code */ 2 X% M% r3 p( r* R& {' b& t4 I4 h}

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

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); 5 e; t& |8 t& t9 ~# H% nouttextxy(x, y, "Press a key to close the graphics system:");

/* wait for a key */ + J2 S+ v$ f2 f; t, h" a1 Lgetch();

/* closes down the graphics system */ closegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); + n5 ` x5 O) G F8 f5 F5 rgetch(); return 0; } 4 T/ V* x5 V" y9 \$ K4 U$ o( Q & G0 y, Q) E" E" \5 S

函数名: clreol 功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 程序例:

#include

int main(void)

{ 3 M/ w2 j& l' `6 a8 f* h7 nclrscr(); cprintf("The function CLREOL clears all characters from the\r\n"); & {+ B9 v, u; D. q8 R3 Q! icprintf("cursor position to the end of the line within the\r\n"); 2 d ]. ^3 @1 _9 K/ \cprintf("current text window, without moving the cursor.\r\n"); " `/ E d" Q, w" }2 e/ Rcprintf("Press any key to continue . . ."); gotoxy(14, 4); getch();

clreol(); ) ^/ D" Q' O2 s# O |: egetch();

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return 0; } + C i2 M: h7 C$ {

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函数名: clrscr 功 能: 清除文本模式窗口 用 法: void clrscr(void); 程序例:

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#include

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int main(void) { int i;

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clrscr(); for (i = 0; i < 20; i++) : w8 n6 _# _8 W9 dcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

clrscr(); cprintf("The screen has been cleared!"); * W5 g5 p, i9 P* L5 }getch();

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return 0; / L2 p0 |0 _/ y9 f. L} 5 Y; l: z. H* n+ q, c( t

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函数名: coreleft & a' Y7 q# x% d; o) G功 能: 返回未使用内存的大小 ' L' x) X* E: j: ]' l; M用 法: unsigned coreleft(void); 程序例:

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#include # n7 ^+ B6 C, @* K0 C#include

int main(void) . Y% M+ Q4 m0 ~! J! d{ printf("The difference between the highest allocated block and\n"); 7 y% x1 c" o$ S/ Nprintf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; 3 R+ w$ u% F* t' b) S}

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函数名: cos 功 能: 余弦函数 ; w& u% \: A0 y: a( W; @* b# G. |/ i) [用 法: double cos(double x); 程序例:

#include , M; E/ Y% q( P0 d#include

int main(void) { double result; / H9 w: l2 J) X6 P. ddouble x = 0.5;

result = cos(x); printf("The cosine of %lf is %lf\n", x, result); return 0; } 7 T+ @9 q& M0 ?, D0 \

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函数名: cosh 功 能: 双曲余弦函数 * H7 d" {3 Y9 \4 w用 法: dluble cosh(double x); & ^. r O2 O7 |. f1 r v5 J5 H程序例:

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#include #include

int main(void) { double result; 9 d4 T9 k. r A4 |1 F) M# mdouble x = 0.5;

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result = cosh(x); 2 `: s4 D: m* f' d& ~, wprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; + N! S$ d' d# f& e. i3 K& K, V6 }} - x$ s" Z n6 w! b

函数名: country * x y6 e$ f2 t! I9 Q2 N功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); ]" y5 e4 |& N程序例:

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#include #include

#define USA 0

int main(void) { struct COUNTRY country_info;

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country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", . V+ D# N6 Z2 |) Jcountry_info.co_curr); , F, V, M& F' h1 Lreturn 0; } 9 { X) A, ^9 w( a+ q8 f

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函数名: cprintf ! v; I. z4 T1 P. U) w1 U2 R& _' |功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); k) p0 V9 _8 F程序例:

#include

int main(void) & ^! B& }, a; m" G/ ]* H{ /* clear the screen */ clrscr();

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

/* output some text in the window */ ! B& z+ F. ]; H% k* }- S o: Xcprintf("Hello world\r\n");

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/* wait for a key */ $ b9 S; {: ?8 q2 w; U' n* i, }: rgetch(); 2 ~& a: l3 O$ F# \$ I q( @return 0; + g4 R* h) U( z3 i8 [8 |} , M) d( o4 E% l( Q# |: z

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函数名: cputs % D! G" b1 {3 J% g功 能: 写字符到屏幕 用 法: void cputs(const char *string); 9 {8 B, _# f. m/ Q9 W程序例:

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#include

int main(void) { /* clear the screen */ ; H3 D7 Q1 ~7 Y( v! b3 ?clrscr();

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/* create a text window */ 0 H y" ^& W z% Xwindow(10, 10, 80, 25);

/* output some text in the window */ $ Q$ s$ C/ E3 H. a2 a, A0 {+ Ccputs("This is within the window\r\n");

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/* wait for a key */ getch(); 2 f' B: u$ Z! R9 R/ @6 |return 0; & q# `# L9 U' H' y- N7 D} 9 g8 D; Y/ O2 y; O1 ~" a. K

函数名: _creat creat 功 能: 创建一个新文件或重写一个已存在的文件 $ t5 C- {" D8 J2 B8 [% f用 法: int creat (const char *filename, int permiss); 9 ^8 K1 n* a; \, S+ I0 u+ j* [- y: K程序例:

#include #include #include # u, c, E/ v3 E! B: G#include

int main(void) - Q. o# z" O: O/ d" R{ ' l& Z/ a/ p3 {9 ~$ H' Pint handle; 5 B4 a* |% Z' o4 i, Wchar buf[11] = "0123456789";

/* change the default file mode from text to binary */ * S6 M, L6 p9 R" ~9 Y_fmode = O_BINARY;

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/* create a binary file for reading and writing */ $ C! M& K; @2 `+ Rhandle = 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* w* l2 J- [ O, h} 7 C, o; a' O. c) ?8 X6 L

函数名: creatnew 功 能: 创建一个新文件 3 X0 U+ [) n" }" E, \用 法: int creatnew(const char *filename, int attrib); / j3 w9 t/ k+ Z" P g( d8 P V4 J# n# {, d程序例:

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#include & N/ c3 T0 @: J- R- T: e# y% f#include % e* Z) [+ f* ^#include : X6 I$ j5 K3 B& w4 ]. Q#include 6 k. z8 J% Y0 J2 ^; o+ b; J#include

int main(void) 2 J+ }2 r+ n; s6 u, H) d/ P{ int handle; char buf[11] = "0123456789";

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

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if (handle == -1) printf("DUMMY.FIL already exists.\n"); 2 E# ]7 C5 J7 l- Y9 P6 Z Z% relse & A$ W% {* e' x{ ; N4 D( c( C: B qprintf("DUMMY.FIL successfully created.\n"); + A* n5 }( E I* M5 b7 K# E! z+ O9 |write(handle, buf, strlen(buf)); close(handle); W* X5 h+ ~) B4 D. M% b} : k' H0 ~/ w9 X, ?3 R0 nreturn 0; } & q2 k9 i3 ~9 j0 Y

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函数名: creattemp - r9 ]8 y$ X6 |- k" ^8 D2 }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 #include + P& r6 c- f$ o) f/ q1 [) K @#include

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int main(void) 3 I: b: I9 i1 E- b) L1 K6 E w7 v{ int handle; ! W Q4 t. b% M4 Hchar pathname[128];

strcpy(pathname, "\\");

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/* create a unique file in the root directory */ ! x+ M* c* X2 `# z' x% H4 ahandle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); 3 {" N4 y* y2 G$ X3 z+ jclose(handle); return 0; & k% N6 G0 ]" ?2 E% G} 6 S3 u( R8 K/ }. J/ ^% L

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函数名: cscanf 3 Z) M( R' m2 g* g1 s8 x8 [: `功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

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int main(void) " O& Q& V. ]7 L{ 0 E" i' ^$ Z- y6 ^5 T9 r: z. ~char string[80];

/* clear the screen */ clrscr();

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

/* read the input */ 3 a& Q- @4 Y. ucscanf("%s", string);

/* display what was read */ ; d I8 X; \, u+ T- p( _/ f2 Ucprintf("\r\nThe string entered is: %s", string); + g, v1 m# {- p, Ereturn 0; } , P# o# _5 T# E- R& v% _- g( w1 P

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函数名: ctime : V8 y/ Y$ J, \& S: b6 _, v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:

#include #include

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int main(void) ' j3 k# _ v% g0 o4 W( t" ~% O{ time_t t;

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time(&t); 2 m! J, K K! J. k2 Q+ Bprintf("Today's date and time: %s\n", ctime(&t)); $ @( P; `. n4 v1 o3 @8 q3 l- x: @7 qreturn 0; + c% _7 j& h8 R8 M" t: G9 o} 7 f: {. P/ T0 h" l( e; z

函数名: ctrlbrk ) W- ^' x' g' ~功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 程序例:

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#include 0 a2 F: X. T+ n% U3 v#include

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#define ABORT 0

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int c_break(void) , K$ F: ?% _* w{ printf("Control-Break pressed. Program aborting ...\n"); $ [- k# h7 p: E' S Jreturn (ABORT); & n: B: z9 C6 |& g% v( e9 c0 b& a}

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int main(void) { ctrlbrk(c_break); 9 Q9 ^9 k& o3 t7 Qfor(;;) " W* O% M. W J0 K3 P5 ` Q{ printf("Looping... Press to quit:\n"); } 4 S6 o0 `1 ^8 c2 N- {# \4 @" L2 ^return 0; }

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