函数大全(c开头)

韩冰

函数大全(c开头)

函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); + I6 }* d' w6 {, E G* S: ~程序例:

#include $ V; X! Y. K* a6 l#include

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int main(void) 2 E. S7 \1 Y5 ^' o{ 6 r5 Z& L8 _6 L- C8 f; Sstruct complex z; ; R; L) z( r3 W$ F" h# } Kdouble val;

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z.x = 2.0; * m% o1 A* O$ a: ez.y = 1.0; val = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); 3 e8 N/ z' e j7 N/ a, _+ }return 0; ) N5 N. i6 f! d$ n& ]$ @! z" o} 6 m" V# U) @) P5 _7 d! C

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函数名: calloc 7 d% X" K( z" ?# T4 S& N功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); $ {1 }8 R7 d1 c" o程序例:

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#include #include

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

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

/* copy "Hello" into string */ ) z7 L9 a( [0 z3 Y# Kstrcpy(str, "Hello");

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

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/* free memory */ / G6 G& o3 p$ D) R/ Zfree(str);

return 0; } 4 k. R- k; O& R# d

函数名: ceil 功 能: 向上舍入 用 法: double ceil(double x); 程序例:

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#include #include

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int main(void) + \* ^6 P6 y% R4 D5 ~8 Y1 G{ double number = 123.54; double down, up;

down = floor(number); 3 I. C# l2 s- f1 b& N" M" Q2 u/ A7 Aup = ceil(number);

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printf("original number %5.2lf\n", number); printf("number rounded down %5.2lf\n", down); ! j. ^+ M% h: u/ t1 S& [printf("number rounded up %5.2lf\n", up);

return 0; 8 P9 d: j' t. U- X% H" j} T' e/ o% s6 D3 a3 z 0 k/ u8 E4 y; d1 x& O$ r" I) v

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函数名: cgets # ~$ h; }: D! n* d; @2 n功 能: 从控制台读字符串 % z' Y; L5 y% ?3 a; r$ q, G3 R( c用 法: char *cgets(char *str); * \% u8 S4 ~: y" A, d, X程序例:

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#include #include

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int main(void) { char buffer[83]; 0 K' S# o ^9 l( i/ K9 Bchar *p;

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

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printf("Input some chars:"); 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 */ * P# F* w! _3 K& q, I3 b7 @buffer[0] = 6;

printf("Input some chars:"); . g% ^& J/ o5 }4 O2 Hp = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); : T+ Z0 ?) L9 N' d' Bprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); 8 r7 m& _; C8 Y c- ?return 0; # s M+ S4 y* ~: [* P) {9 E} ; J- S" {. d4 l4 ^: w3 E . x6 q) S! z" \6 B- s3 S% \

函数名: chdir 6 `; h2 k% d5 |8 h I( E' S功 能: 改变工作目录 用 法: int chdir(const char *path); 程序例:

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#include 3 A' C% z9 P) b( ]. \7 z#include #include

char old_dir[MAXDIR]; % b9 q- ~8 l1 S8 U/ jchar new_dir[MAXDIR];

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int main(void) ) B! B! r7 c8 X0 {& b: d{ ; Y0 \, e5 X/ c7 d. n; ^if (getcurdir(0, old_dir)) 7 N H9 s* R! I2 X! N P{ perror("getcurdir()"); " w+ e/ X" N0 ]( C. L7 {exit(1); } ! n3 ]3 p7 C2 s1 Yprintf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) { perror("chdir()"); exit(1); ) `. B) Y% S' j( B}

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if (getcurdir(0, new_dir)) : ~' O- q/ U- ~" H8 ~{ % I8 J7 e1 i! ?5 D# z# S) Z& g' y3 aperror("getcurdir()"); exit(1); } ) ]3 L% \; J. L; O, z8 N. o! Wprintf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); 3 f/ \- q* H/ o, e, V- N. K) hif (chdir(old_dir)) ' z* w! D& E! Z5 j3 W7 p{ perror("chdir()"); 5 q2 P5 ]0 }2 p0 N5 }2 texit(1); 6 r- s; z5 t9 Q3 v# s# s! o* F}

return 0; } 9 X2 s& u3 E7 V: G6 \

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函数名: _chmod, chmod o4 f7 N* a. U0 }, r功 能: 改变文件的访问方式 用 法: int chmod(const char *filename, int permiss); ' t& a2 m) ]4 K0 ~7 G! G程序例:

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#include ' ^" l& L" @4 x7 ^#include #include

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void make_read_only(char *filename);

int main(void) 4 q; D; @5 z- \1 X4 E{ make_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); ( W- G7 D( H2 X* F. n# C# s4 n8 A ?return 0; }

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void make_read_only(char *filename) ! z! i1 i: [# [, h5 p9 [7 P; J{ int stat;

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stat = chmod(filename, S_IREAD); 0 H! S, C$ ]0 b# l3 J( c, J7 wif (stat) & ~; ~9 {" X6 a) ~ mprintf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); - M5 S* l6 r C7 Q3 ]} ; Z+ M* y2 K1 R3 j* W% ^ * b# v/ u2 X7 D8 a* x# o: \ w

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函数名: chsize ' }8 B/ I- T3 e, B s功 能: 改变文件大小 ( G1 M) O9 c1 j2 b用 法: int chsize(int handle, long size); 程序例:

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#include 2 }+ C2 o9 f) }+ k. B- G0 I2 k#include #include

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int main(void) & T! E. c2 C7 R: ~{ int handle; , l8 {: |$ }8 v* q! y% Rchar buf[11] = "0123456789";

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/* create text file containing 10 bytes */ ' @' G' W- B8 y- T* g3 I: ihandle = open("DUMMY.FIL", O_CREAT); # Y- R) l4 S" O: j, X8 ?. P$ ^write(handle, buf, strlen(buf));

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

/* close the file */ # k6 N5 O8 H2 l/ b7 c8 d d3 p' Dclose(handle); 8 L/ Q; H8 S" o4 f9 g3 n, @. j8 xreturn 0; } % {1 T5 F0 r [9 q# d5 g( g

函数名: circle - E& T# x4 e+ q3 r. }3 T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:

#include #include #include #include

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int main(void) " A: {1 P5 u# Z9 v{ ! H6 J% @' C+ n8 x# N/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int midx, midy; % O* Q5 P0 F, t9 Iint radius = 100;

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

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/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { 4 a6 t+ }4 b' i+ D3 H# P9 ?printf("Graphics error: %s\n", grapherrormsg(errorcode)); @1 p# W- D7 d. ?; N9 l3 aprintf("Press any key to halt:"); % I/ ~- R% k8 N3 N# S# ugetch(); 4 q9 H) e- m. e/ C2 T- Mexit(1); /* terminate with an error code */ 7 s' ` M- m$ I+ \# ]}

midx = getmaxx() / 2; " [ b6 R4 i$ x, I2 D+ qmidy = getmaxy() / 2; setcolor(getmaxcolor());

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

/* clean up */ getch(); closegraph(); return 0; } 1 w% D4 |6 g" C( | 5 ?2 A. A! h* M4 `# L4 z

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函数名: cleardevice 7 ~# c7 y% |& O; l6 T8 N功 能: 清除图形屏幕 用 法: void far cleardevice(void); # k- ], w( N. Y' }* U+ G2 L程序例:

#include #include . ~9 Y) z: [0 ], V( L#include 8 \5 ?$ S, \9 O0 b2 y+ W#include

int main(void) { ' ]1 Y: M8 T+ ?! E/* request auto detection */ : f# w- F2 A2 n* B0 @int gdriver = DETECT, gmode, errorcode; ' w5 i% J( [0 f7 o, [# m% c4 E, Zint midx, midy;

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

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ! X2 g0 ^$ J* ^ M1 T# A- D) N, U{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); * g r, K0 I# |3 {9 c6 x/ G) hprintf("Press any key to halt:"); getch(); 7 \0 k, J4 g6 }) @. dexit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; * o3 M8 e% V- ^" Y# y- _8 wmidy = 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:");

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

/* clear the screen */ cleardevice();

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

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/* clean up */ getch(); closegraph(); return 0; + G3 Z6 A$ l1 L& y" t+ b% `" w1 @} , Z' ]! F1 V" L$ P5 K ^ 2 v$ I% k1 L; ] D! F1 C6 v

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函数名: clearerr 功 能: 复位错误标志 D1 I0 t6 ?9 x" `" ]% e用 法:void clearerr(FILE *stream); & N& b8 k% r- b8 c i8 R# b程序例:

#include

int main(void) { 6 A' H' p# T4 o; I) N0 cFILE *fp; $ f4 E$ w6 X8 B2 Q P4 d& ichar ch;

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

/* force an error condition by attempting to read */ 5 U" @2 ~5 D3 `$ O5 R# ych = fgetc(fp); ; @) H1 h* l5 ?9 j: k' g: mprintf("%c\n",ch);

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if (ferror(fp)) 7 l" |9 E$ s* w{ 0 ^5 t' d {1 d. H' w* ]5 x/* display an error message */ 8 Q. I% h$ _5 F, H1 x" r: b9 Y# qprintf("Error reading from DUMMY.FIL\n");

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

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fclose(fp); return 0; } 7 M9 P- k/ D" c2 E. S. E

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函数名: clearviewport 2 B8 _; b' y% v9 W9 X功 能: 清除图形视区 , n' b, d$ Y0 t' e( R; d' ^5 P0 [用 法: void far clearviewport(void); 程序例:

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#include 3 ^- h! c% ~9 p# _! p3 k4 c#include ! z# Z+ R) r r#include ; k. F3 B+ }+ I#include

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

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int main(void) 0 @8 A. j% ^6 a! }8 |# Z- o/ Y{ $ j5 f* z7 x8 E/ Y1 d# u/* request auto detection */ 3 P. ]$ |5 A$ _ c( m% p3 mint gdriver = DETECT, gmode, errorcode; int ht;

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

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/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { % c9 A& }( Y. p& N0 X' zprintf("Graphics error: %s\n", grapherrormsg(errorcode)); . D8 \1 ?, [7 K6 x9 Rprintf("Press any key to halt:"); getch(); . W/ N. T- k6 `" u5 ?# U# X0 \1 Mexit(1); /* terminate with an error code */ & ^. Y. d' D+ w3 @}

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

/* message in default full-screen viewport */ 6 C+ J' j' w' X: v+ Wouttextxy(0, 0, "* <-- (0, 0) in default viewport");

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/* create a smaller viewport */ 0 t! O9 w, ]4 N6 Usetviewport(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:");

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

/* clear the viewport */ 7 Y' @7 e5 l0 R: iclearviewport();

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

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/* clean up */ ! P7 y4 C. q; c. q) e! L2 _getch(); % i" x& b# b* M, U6 E: t* Qclosegraph(); return 0; 5 Q/ {* t% u, x+ T} $ g# |) P: q m7 z6 i9 P5 u & z* O$ z! @+ x- K" v* F6 y% F2 \

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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 4 a! r P% o1 V' W0 E# g4 N0 r0 N#include

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main() * s% D; W' e ~6 i8 B{ int handle; char buf[11] = "0123456789";

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/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); if (handle > -1) 4 N3 [. c1 h1 ?/ [: ]2 x{ write(handle, buf, strlen(buf));

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/* close the file */ close(handle); ! V0 l8 h/ ?1 p% ~1 m} else " b4 }0 D" t$ D9 w9 e0 ?{ printf("Error opening file\n"); } 4 a" u; q! `! ]* i) A5 N6 Zreturn 0; 2 L2 h: |5 `4 u2 E" d+ G} 8 U- ]7 `; s' @0 q " L4 x. B/ h' l$ G; X" P

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函数名: clock , ^$ I" P9 L& s! G0 n% k! }功 能: 确定处理器时间 1 q8 S; f' ^! p/ o# s用 法: clock_t clock(void); 程序例:

#include & [& s* ^6 a( N4 v8 l5 C! g#include #include

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

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delay(2000);

end = clock(); 0 X$ V$ l" A+ T; w$ b' pprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; 9 U4 k- Z' F9 X0 m* Z7 O# `} ( n% b/ D# k' @" ` 6 `( I8 g4 o8 k

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函数名: closegraph 功 能: 关闭图形系统 + }" y6 {7 Y$ N用 法: void far closegraph(void); : t7 A, D0 t! v$ ^程序例:

#include + w# ^) K: ~* a1 V#include 0 o, g" ]+ v# m- A# p/ A8 ^5 u#include $ m& X- V* A7 `, o( I) b: T#include

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int main(void) * u# u, |0 R) B, N{ ! _* P; z' N, Z8 b+ ~ C/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int x, y;

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/* initialize graphics mode */ t: l$ D) @! U" Ginitgraph(&gdriver, &gmode, "");

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

if (errorcode != grOk) /* an error : e V1 Y0 s9 }& I: Eoccurred */ { $ \/ ]1 V/ ^1 n9 k3 e( nprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); ! @4 C4 c* d/ F2 qgetch(); : W; I+ Y& }' D; g5 Rexit(1); /* terminate with an error code */ }

x = getmaxx() / 2; 5 a8 A( z. c6 |9 zy = getmaxy() / 2;

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/* output a message */ + z! C8 ~2 M& |settextjustify(CENTER_TEXT, CENTER_TEXT); # m6 r6 \5 P' X+ I! [- O! souttextxy(x, y, "Press a key to close the graphics system:");

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

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

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printf("We're now back in text mode.\n"); , I5 o2 t9 c2 ?5 i5 nprintf("Press any key to halt:"); ' R- }4 U' x4 [: V" g4 Vgetch(); return 0; }

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)

{ clrscr(); + U! J/ ~. ?8 f0 \4 L/ Acprintf("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"); cprintf("Press any key to continue . . ."); 6 \9 T8 N( Z# p; A* o1 ~1 z8 Bgotoxy(14, 4); * u9 q! @# o/ @& }+ [getch();

clreol(); 0 k( x. R$ V/ r% q, Ngetch();

return 0; ( _" |6 d/ v4 I" r5 o/ J} ! k4 O. m1 @+ T- L$ [* _

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函数名: clrscr / r, P4 W: V) ~+ u- }( Z# q* [功 能: 清除文本模式窗口 0 q- Y! t3 Y% }9 G( a$ \用 法: void clrscr(void); 程序例:

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#include

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int main(void) 1 [& y1 n2 [, q- X{ $ K1 f7 q# a) s% I7 n2 ]int i;

clrscr(); 6 l: g, z1 X) f0 Xfor (i = 0; i < 20; i++) / p+ k" N/ ^: a6 D6 h7 S p% ]cprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

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clrscr(); cprintf("The screen has been cleared!"); getch();

return 0; $ ~% U! e; B0 ~5 } D0 d6 j. n} _ N" E0 G3 Z/ z z; t( H' { ' L. a! J4 |8 w! d6 P0 Q z/ \

函数名: coreleft 5 C. d, C$ W3 a, P5 J* B功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); 1 z/ E" M4 U J# N程序例:

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#include #include

int main(void) { $ Q7 |9 P7 F6 @4 J4 ~! N+ `( V6 vprintf("The difference between the highest allocated block and\n"); , V9 [: k' I( C0 J) `) Pprintf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

return 0; + F0 ~- w* c& x5 j9 K3 f* T. v}

函数名: cos ' I; {" q+ \3 n3 X1 O$ K1 k功 能: 余弦函数 用 法: double cos(double x); 8 J" p; u+ l9 m" ~程序例:

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#include ) R0 U, y4 u. E#include

int main(void) + h _/ M7 u" l$ Q, M* A1 {; a: N{ double result; / u" H6 _+ i5 C7 Tdouble x = 0.5;

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result = cos(x); 3 r- V) r' l+ p" k& {$ }' cprintf("The cosine of %lf is %lf\n", x, result); ! i! |4 r: P; X- U( L* d% Sreturn 0; } 4 o% E; N: K2 { _1 r) B$ L* v

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函数名: cosh ) R8 N+ j7 ~0 y2 j功 能: 双曲余弦函数 ( H! ?/ b3 u; Q用 法: dluble cosh(double x); 程序例:

#include & z7 d0 Z. _5 q2 {# R! b#include

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int main(void) { double result; double x = 0.5;

result = cosh(x); 8 U' I; s t9 G2 s- Rprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; } ; }( Y, \( m" k; K/ c6 k' X. w $ s0 D. }- K; a% j) e) W $ g9 x; V! P# w4 K9 B

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函数名: country % J t+ V _' f' V. n功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); % T& U9 b2 U+ V2 k程序例:

#include 0 Q5 Z4 i8 L$ I& _; W/ [#include

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#define USA 0

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int main(void) 3 e+ B' ~; ~% u' b' S: d{ # N" v( F+ @! b' L6 e! z, f% ]struct 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); # v( B* ]& |5 t7 y# ^2 qreturn 0; 5 ~! s' w' \3 g# W Q# w* I}

函数名: cprintf ) k* m0 F8 j( m功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); ' a; p& Q* @8 `5 r程序例:

#include

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int main(void) 0 q8 @: S6 @7 {' }3 _: }9 g2 {{ ) h; n8 O/ ? k/* clear the screen */ clrscr();

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

/* output some text in the window */ : X1 c9 r# p! Q! M& K- Acprintf("Hello world\r\n");

/* wait for a key */ getch(); + B: k) x. W% U4 wreturn 0; } 9 X- Q/ j6 Z, H% K% r ; _$ k8 `0 K& ]5 b! j 2 ?: w$ C1 b8 T8 f0 w+ |

函数名: cputs 功 能: 写字符到屏幕 用 法: void cputs(const char *string); 程序例:

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#include

int main(void) { 2 q& e% B5 `6 m3 M+ d/* clear the screen */ 8 [. X) y, w! ~. Q6 g. X% q4 rclrscr();

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/* create a text window */ , F: u( N. l4 k9 R6 X( }6 O% l8 \window(10, 10, 80, 25);

/* output some text in the window */ " s6 ]& f; i }3 g, E; pcputs("This is within the window\r\n");

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/* wait for a key */ , h% T4 T4 p2 s0 y3 z9 ~2 Vgetch(); return 0; } & i4 k6 K: x$ y' B. ]; j- C/ K

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函数名: _creat creat : h( A; m9 Q, `; ]: [* M0 \+ n功 能: 创建一个新文件或重写一个已存在的文件 : o( h8 z& k0 ^0 c, |8 u用 法: int creat (const char *filename, int permiss); 程序例:

#include #include #include #include

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int main(void) { ' o/ l3 ? D5 V3 Z- }int handle; char buf[11] = "0123456789";

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/* change the default file mode from text to binary */ $ ^6 t( }" y ^4 E/ a_fmode = O_BINARY;

/* create a binary file for reading and writing */ : }) }+ d$ E! o* {; r& O u( }handle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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

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/* close the file */ 8 f; p6 H* z* X0 rclose(handle); ) l! l( @5 K. I( [ }return 0; }

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函数名: creatnew , z) D* ~' J i* a/ L$ L( D功 能: 创建一个新文件 7 h+ ^; q, B8 X: `+ O* J用 法: int creatnew(const char *filename, int attrib); 5 S" T Z$ q7 G8 f2 B: S, k程序例:

#include 6 ^9 O9 K5 L9 l/ E#include - g2 ?& G* R: Q/ R. k4 G#include #include #include

int main(void) 5 F8 E" I, V, }7 O" N5 x2 U{ # E' \+ W6 M, [5 l( u- }% Pint handle; char buf[11] = "0123456789";

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

if (handle == -1) ) y% d: d. `' j8 s% ~" Gprintf("DUMMY.FIL already exists.\n"); else 3 r4 q) w& \6 j{ 0 [% M; q3 s! ?printf("DUMMY.FIL successfully created.\n"); + T, N$ ]. D4 fwrite(handle, buf, strlen(buf)); 4 D4 r& y- O4 N+ Zclose(handle); } ) Q; P) m7 [5 S; n- nreturn 0; } 7 }# j, x- `$ b

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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 ( ^8 [9 V' {/ L* h& [- G. i; i用 法: int creattemp(const char *filename, int attrib); a2 a. B& ?1 R" {5 r) |程序例:

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#include #include #include

int main(void) 6 w4 B% W( G G6 [" o% t! W |! C( U{ int handle; char pathname[128];

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strcpy(pathname, "\\");

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/* create a unique file in the root directory */ : x* q8 ]1 k! E/ v7 ]handle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); : w% v2 e) x. J1 N& g0 E' |close(handle); return 0; * ?8 P/ ]/ f0 }/ e# F} 5 k$ }4 O T% Y1 t2 s( k. a; }

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函数名: cscanf 7 @2 t2 W3 I1 h8 o功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); 程序例:

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#include

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int main(void) 4 c$ h! a7 u: j2 k{ # ~3 A9 v+ y) [1 b7 R+ ychar string[80];

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/* clear the screen */ ' {; `; E4 c: T6 W. @ P! Wclrscr();

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

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/* read the input */ 9 g' T$ t* W. E" X& a4 u. ccscanf("%s", string);

/* display what was read */ 8 @8 J. y6 `7 t: Mcprintf("\r\nThe string entered is: %s", string); return 0; : _5 M3 u) M" h3 @} 6 j+ W2 ~ X" \" W% e! R9 h7 n # b: @) p" Z3 B& h4 n+ g

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函数名: ctime J7 T5 W/ j& C9 R功 能: 把日期和时间转换为字符串 用 法: char *ctime(const time_t *time); . i+ W6 J: u+ h# _! y, d8 _& p程序例:

#include #include

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int main(void) ! A( ^! i5 q8 m& x0 a- t{ * b5 S. s( J3 P" [. Ptime_t t;

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time(&t); ) }3 \ ?) d9 N h+ G, L0 Vprintf("Today's date and time: %s\n", ctime(&t)); return 0; }

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 1 S! J1 e: I3 G% r用 法: void ctrlbrk(*fptr)(void); ; Y0 q4 P* b; U% m, r& P9 Y# D程序例:

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#include ) e/ U: g/ k$ Y#include

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#define ABORT 0

int c_break(void) { printf("Control-Break pressed. Program aborting ...\n"); $ ~- J! V" i$ k* D9 d. W; Treturn (ABORT); }

int main(void) & p! Q9 B4 k- s( X! S" V" V1 W( I{ ctrlbrk(c_break); for(;;) O3 A! C& i" N' d{ printf("Looping... Press to quit:\n"); + d: Z" k* v2 T& m# e' B4 E! z8 ~} 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