函数大全(c开头)

韩冰

函数大全(c开头) 5 `% t, F* u7 t0 f3 b- j/ ?

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函数名: cabs W3 k' x" g5 s d; s% G功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 程序例:

#include * L/ B& D7 [2 Y/ `#include

int main(void) ) D: c' ^! C6 T1 g* q( q{ struct complex z; double val;

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z.x = 2.0; z.y = 1.0; 1 J. A! f5 X! d) M# g' dval = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; ! b) }% @" U @/ J9 g9 ?' _- q} $ y1 @4 E9 ~6 B, g; |- O ! E+ _/ H' q9 z0 @

函数名: calloc 6 Q& [1 ]; \5 C, W6 p# n功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); . K: u& \# K. G7 P; {) _* ]+ C: a程序例:

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#include #include

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

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

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/* copy "Hello" into string */ ( s6 Z% Y& A- P# istrcpy(str, "Hello");

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/* display string */ , S& o1 w l3 q+ d9 Jprintf("String is %s\n", str);

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/* free memory */ / {3 f( Q4 l/ `$ ^6 R# gfree(str);

return 0; 8 s4 A$ f- Q0 z9 B/ M! E0 H} 6 w X7 u7 o* ~/ s! Y- S' i' q: ?- R ; q; k) r3 ]! A9 |$ M4 F: i: l/ r# z - g4 d! P& u4 P8 X

函数名: ceil 1 m: \: p/ K, x; _0 ^& h功 能: 向上舍入 5 |7 q% ?, r+ c& U# o用 法: double ceil(double x); 程序例:

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#include ) i( \5 m) T+ ?4 @9 Y2 y0 O( e#include

int main(void) { double number = 123.54; 5 w6 k+ i0 F; v7 ~0 Hdouble 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); printf("number rounded up %5.2lf\n", up);

return 0; } . u0 I8 ? b' d

函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); - \ C2 i9 C$ @+ R程序例:

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#include : P; W) m! E5 I \+ `#include

int main(void) { char buffer[83]; $ x2 A8 A4 Z8 x% Q: @4 U: Ychar *p;

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

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);

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

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printf("Input some chars:"); p = cgets(buffer); ' E# I& D9 w" E8 H, {printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); ! M) k7 N; z1 s3 Z, S2 freturn 0; } - `: U4 y; ~% H

函数名: chdir 功 能: 改变工作目录 # ~8 W% u+ ]6 e. L# m. q5 ^用 法: int chdir(const char *path); + \! S! K- }2 b' ?7 e7 P程序例:

#include #include #include

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char old_dir[MAXDIR]; & @7 }+ j0 H: {8 E: T8 k$ wchar new_dir[MAXDIR];

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int main(void) / C) l: H4 m+ Y2 k: Z% f{ 6 N6 T5 @* V" i' I4 p6 aif (getcurdir(0, old_dir)) ]: t# j# v2 z) k! p: i{ 4 \2 v0 O' v( Q' s6 T! ?& Eperror("getcurdir()"); exit(1); 8 ~0 k9 i3 S! U9 @9 X" v} printf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) ; Y% U+ [4 h. L5 X$ Z3 Z{ # d; w4 d9 V& a' Z. r A% u4 Hperror("chdir()"); exit(1); % {0 k( d5 `- C+ y- @}

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if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); # m6 ] ]) A1 V! j} printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); . R' F# E% n9 G3 E! X/ q9 Pif (chdir(old_dir)) 6 [+ U# ?8 z4 }. ] U6 d E{ perror("chdir()"); 4 B2 l$ \, c) {9 v7 I; @+ hexit(1); ! a# d8 Z- r9 p6 }}

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return 0; } * I- W$ h t7 i I) L , o! `. x2 C9 L2 X; \, }+ Q

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函数名: _chmod, chmod 功 能: 改变文件的访问方式 ( f1 J& h2 ]3 I' @9 \) J% g7 N2 L B用 法: int chmod(const char *filename, int permiss); 程序例:

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#include ' M( C1 |4 X9 X. B) ], Z, M#include - F0 p; p: j8 K- b' Z4 s; |% h#include

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void make_read_only(char *filename);

int main(void) , f' I" _ K- e4 `7 P{ make_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); : }3 c' A! i+ L( Freturn 0; 5 L k3 Q* [) ^/ `% `$ [+ H}

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void make_read_only(char *filename) ! U3 N1 i, j- F- d4 R* c{ int stat;

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stat = chmod(filename, S_IREAD); & D+ n- a" {4 U; q2 J) x7 B3 P4 {# ]if (stat) # |/ A# ^0 I9 lprintf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); $ c9 [# V5 q. d0 T# w" j3 h- H} ! D9 w2 x! o7 H) @

函数名: chsize - p- `5 @% a, @# W功 能: 改变文件大小 ' F, L7 x% N& C9 L用 法: int chsize(int handle, long size); 程序例:

#include 1 d& h n! K p" U0 P3 m g* a#include 0 ]% z8 z7 e! ?8 h#include

int main(void) 6 y8 i7 I6 N2 g* C{ ' {( Q# r& K9 \0 yint handle; char buf[11] = "0123456789";

/* create text file containing 10 bytes */ 9 l. K4 T! ^* J. L9 ghandle = open("DUMMY.FIL", O_CREAT); " G4 v: R8 d1 N# C: Pwrite(handle, buf, strlen(buf));

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

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/* close the file */ * _9 h4 _: V0 O) Q* ?close(handle); return 0; . d9 k- r1 x5 R3 _3 I} 6 g/ c7 p* R/ ~) i: L8 ?" J; {2 b! `

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函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 用 法: void far circle(int x, int y, int radius); ' a0 d0 Y* T- n4 f" o- C; p# }程序例:

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#include #include #include , Y6 h' b7 y# f" b& b#include

int main(void) & h, Z" B# ?' x' {5 _{ /* request auto detection */ % p7 Z0 _- R, R; P6 x7 |int gdriver = DETECT, gmode, errorcode; int midx, midy; # c. f4 M, R! o# t T4 jint radius = 100;

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/* initialize graphics and local variables */ + |$ C- M* F8 ~- S9 r" Sinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ( g! v! x. u: B8 P$ I0 o! M5 derrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ ' A, F- H c5 O# f9 Z" w{ 6 k8 }+ x! B" r; V% Y# o& |# r& Sprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

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

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/* draw the circle */ 9 |$ w x1 U/ ]$ V6 acircle(midx, midy, radius);

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/* clean up */ , r. S) F" |+ m. y! p/ P% Xgetch(); closegraph(); # p' x: Q" U1 Mreturn 0; } ; h* X0 E! f( r

函数名: cleardevice 功 能: 清除图形屏幕 8 H+ @1 [) a, ^2 M6 x) ?7 J用 法: void far cleardevice(void); 程序例:

#include #include ' ^ v6 u6 X7 b9 z8 K8 c#include #include

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int main(void) / m; X6 ^& e' P# R0 Q. c8 @{ /* request auto detection */ int gdriver = DETECT, gmode, errorcode; 9 b$ u* C! j0 J4 c3 Uint midx, midy;

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/* initialize graphics and local variables */ ' P4 e1 q% y) @* y( i1 Jinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ " t; w) p0 V9 D. R% Z) Aerrorcode = graphresult(); * D" h) K+ J; i7 O( Qif (errorcode != grOk) /* an error occurred */ & }* A" C% x L{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); 3 d$ _5 `: f9 N5 x' M1 n, xprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; ( C0 ^5 o8 Y3 ?( ^2 lmidy = getmaxy() / 2; c, {! k9 e! R% Esetcolor(getmaxcolor());

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

/* output a message to the screen */ " j4 V- M4 W) u& M6 \6 T7 Oouttextxy(midx, midy, "press any key to clear the screen:");

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/* wait for a key */ , T/ N- y& s, [+ F9 hgetch();

/* clear the screen */ 6 ?3 R: Y/ F M/ ~, K4 X/ Qcleardevice();

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/* output another message */ ) o1 q8 _: f$ T& W# uouttextxy(midx, midy, "press any key to quit:");

/* clean up */ getch(); ' e" n$ P4 \8 C8 ^ wclosegraph(); : a% I" r! f* W5 i& c. z ureturn 0; } ) c' {+ u! Q3 d x

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函数名: clearerr 功 能: 复位错误标志 用 法:void clearerr(FILE *stream); ; g7 Y* |3 V- J程序例:

#include

int main(void) ' L7 Z* |/ O6 R& O{ FILE *fp; char ch;

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

/* force an error condition by attempting to read */ ch = fgetc(fp); ) C/ @* \( G* G3 r0 |9 nprintf("%c\n",ch);

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

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

fclose(fp); / y/ [4 {/ F! f( m6 _" ?& T( s9 treturn 0; } + L& C4 ?: [6 C4 w

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函数名: clearviewport 功 能: 清除图形视区 用 法: void far clearviewport(void); & B2 o& i4 [% k; I程序例:

#include #include #include 3 P; M! j3 h! W+ t0 X c& p6 ^#include

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

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int main(void) 4 {% ~7 A$ R5 A4 w& ` x$ C$ z{ /* request auto detection */ int gdriver = DETECT, gmode, errorcode; int ht;

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

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ 8 o2 P- z# K& A{ ; R$ P( {* D$ s c' _printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); 7 f2 t& K: z9 h) Cexit(1); /* terminate with an error code */ + F p0 Q+ g. ~. Y7 ^}

setcolor(getmaxcolor()); ; W/ K+ M# v; M4 E* P: B3 Y9 ght = textheight("W");

/* message in default full-screen viewport */ 6 a* h; b& F+ w9 k1 R* }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 */ 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();

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/* clear the viewport */ clearviewport();

/* output another message */ - T% n# y, {" ^& K' [outtextxy(0, 0, "Press any key to quit:");

/* clean up */ 3 |' W) Y: a0 X+ d( ~getch(); 4 g0 Z4 _; q. Uclosegraph(); return 0; } ! c7 |8 n' t/ |# P2 z5 P

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函数名: _close, close 功 能: 关闭文件句柄 用 法: int close(int handle); " m2 I) H4 V% {% B5 F; R/ K程序例:

#include #include #include #include

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main() { int handle; ; k$ |2 f4 ]! {, c/ D6 uchar buf[11] = "0123456789";

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/* create a file containing 10 bytes */ : i. s4 O3 R6 @; bhandle = open("NEW.FIL", O_CREAT); if (handle > -1) { write(handle, buf, strlen(buf));

/* close the file */ ( n0 ?: d, w/ {/ A) o7 ^ gclose(handle); ' ]- O( ?! s# i. z} else { 5 n. b6 E% p& D2 C" _$ Wprintf("Error opening file\n"); } return 0; }

函数名: clock 9 Q H3 D# J" L2 N功 能: 确定处理器时间 用 法: clock_t clock(void); ; _# w% @$ X( [4 }) Z程序例:

#include + S3 n8 p* [" [5 w- J ^#include #include

int main(void) 6 [" f7 N3 l; {% }- I/ H{ clock_t start, end; 7 x5 Z [+ |3 _: w3 Astart = clock();

delay(2000);

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end = clock(); - t7 `: F+ m1 q, M1 c Qprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; } - c3 T( o/ d2 |, H) Y

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函数名: closegraph ; S0 f% \8 Z. r功 能: 关闭图形系统 ) R% c6 I- u3 T* x& e用 法: void far closegraph(void); 程序例:

#include #include #include #include

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int main(void) { % b, W' P. B& X& \0 y# `/* request auto detection */ $ r# T) ~+ b. i% u ~- ~! q" h; {int gdriver = DETECT, gmode, errorcode; int x, y;

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/* initialize graphics mode */ $ ?( {/ ]3 F& u1 j$ R( Pinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ 1 ]- ]- `, [6 M! v: merrorcode = graphresult();

if (errorcode != grOk) /* an error * s+ n7 J% e ]! Foccurred */ { ( D! _8 f$ y; a% B1 f( E$ ^printf("Graphics error: %s\n", grapherrormsg(errorcode)); - l4 T; L. U. r$ i; bprintf("Press any key to halt:"); ]+ U4 K8 t, |8 M# Igetch(); ' l* Q0 ~, ^4 w& iexit(1); /* terminate with an error code */ }

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

/* output a message */ 4 w) u1 `8 h$ m4 Ysettextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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

/* closes down the graphics system */ H* h' W8 E3 H- Nclosegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); return 0; & X* D- @/ M% @# m3 q} 6 H( d# N- Q" e8 G5 p: s 6 u* ~7 |/ n. I8 |. l% v' C

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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); 7 H$ y6 h% P/ }9 h' W程序例:

#include

int main(void)

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{ 3 P: q0 Z9 w3 B5 P- _# m7 p7 m2 nclrscr(); cprintf("The function CLREOL clears all characters from the\r\n"); 4 e6 n9 E, D& S- h1 ~9 ^# ycprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); E9 l8 s" v. [4 O, dcprintf("Press any key to continue . . ."); 8 m% m: Q3 z* }. G) {4 e$ v7 igotoxy(14, 4); getch();

clreol(); getch();

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return 0; 6 O4 o1 Q) g) F$ I& }0 F# l} ; d, h7 A, |% i) ^

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函数名: clrscr 功 能: 清除文本模式窗口 用 法: void clrscr(void); / Z: ]# N! p E程序例:

#include

int main(void) ) S6 o. ~9 |/ f4 l: [8 g9 u+ z{ int i;

clrscr(); for (i = 0; i < 20; i++) . G6 w! S' k3 \/ i* Z( Kcprintf("%d\r\n", i); : b7 s6 w, w) a, S8 L/ \: w7 O6 Acprintf("\r\nPress any key to clear screen"); : g) c# i" M! dgetch();

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clrscr(); cprintf("The screen has been cleared!"); 5 Q1 v" A" U2 r6 z* N) S" Sgetch();

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return 0; }

函数名: coreleft 功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); ) E; c: |$ w, _5 m: M# O程序例:

#include #include

int main(void) 1 E. C! a L) [% H6 Z8 d. h{ 8 [1 ~4 U- |& \2 C9 ?printf("The difference between the highest allocated block and\n"); printf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; }

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函数名: cos q9 Q) }6 D" Q8 U7 y( H功 能: 余弦函数 7 w' ?8 b2 G! s4 n# ~0 U用 法: double cos(double x); 程序例:

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#include #include

int main(void) { : E9 M" f; K5 l, t4 l$ Gdouble result; , D5 V; w' p9 z7 tdouble x = 0.5;

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result = cos(x); % N k7 D( _- V# V% S* {, pprintf("The cosine of %lf is %lf\n", x, result); ; J4 f2 P9 N" r6 c; b- p* ereturn 0; / S- W2 V! Q" t% y1 N. T+ B} . i# [7 p- y8 R6 ? K % h# }" W* |5 p$ ` . p+ v1 ~- O! f1 q" i# }: x

函数名: cosh 功 能: 双曲余弦函数 8 s; z, v" J9 Y用 法: dluble cosh(double x); * K1 W+ Y) X! W, I% ^4 Z, S; Z m程序例:

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#include 8 M' P$ D9 M- l5 g- A- Q9 C#include

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int main(void) { 1 t% ^5 M; ^1 X; Odouble result; 7 S3 p$ \/ }3 `7 b2 g; pdouble x = 0.5;

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result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); 8 M7 R0 @( y" Y9 G" greturn 0; 2 P7 c. P9 i6 v* N% h}

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函数名: country 功 能: 返回与国家有关的信息 % u& W/ \( k3 j+ }用 法: struct COUNTRY *country(int countrycode, struct country *country); ) M* s7 F. y# w$ E! S程序例:

#include #include

#define USA 0

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int main(void) { 9 c3 ]0 ^" K1 ~4 a2 `struct COUNTRY country_info;

country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", country_info.co_curr); return 0; 1 i- G4 M7 O$ b0 i} # Z1 R1 M* C6 M+ i# S ' M$ \4 p0 i: t% }( ]+ d, m: V/ l

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函数名: cprintf - {+ t. T6 G- G0 Y* v; F i功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); 程序例:

#include

int main(void) { # I. l3 K0 O' m0 T/* clear the screen */ 5 }- T4 P) h) ~clrscr();

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/* create a text window */ / ?* R7 L5 V/ a$ l- v2 h7 gwindow(10, 10, 80, 25);

/* output some text in the window */ 0 t( u' W4 ^' B: acprintf("Hello world\r\n");

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/* wait for a key */ getch(); ; u$ ?* W( B. z0 Vreturn 0; ; d! |% J' m8 j f. \} ! k9 O$ {8 }6 ~& [: T

函数名: cputs & j. K! x. k: s4 H6 M+ b功 能: 写字符到屏幕 用 法: void cputs(const char *string); 7 J, d: g5 T! h9 Z0 p2 z8 L程序例:

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#include

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int main(void) { /* clear the screen */ - j1 r( h4 G, T8 ~clrscr();

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

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

/* wait for a key */ getch(); ! f7 b7 H, [" @# T: @. w# ereturn 0; } 5 q3 |, _$ b% ? 5 R$ V1 j6 h5 F- ^, R . B$ S l! w: f$ Z% W

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函数名: _creat creat " C: B. {% [* r- m6 z Y K功 能: 创建一个新文件或重写一个已存在的文件 6 u: o9 b, ^+ U# j用 法: int creat (const char *filename, int permiss); 程序例:

#include 1 K# n* S" }- r#include 9 N3 c( t t0 I8 C0 `3 Z: V. a% j$ K& ~ e#include #include

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int main(void) { : k8 q! V! `: ?# x7 R: T* ]int handle; 6 l7 D2 S) m9 [9 l, M$ R kchar buf[11] = "0123456789";

/* change the default file mode from text to binary */ 0 R& ^: h0 b4 B_fmode = O_BINARY;

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/* create a binary file for reading and writing */ ; B% _: h P# jhandle = 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); 0 }! p% t0 Y8 ]3 nreturn 0; * N4 T9 Z" i- Z+ X# K} 6 A0 q4 {- } X1 C& m

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函数名: creatnew 功 能: 创建一个新文件 # S) t8 U% r+ I8 C" r: |; s用 法: int creatnew(const char *filename, int attrib); " K C, X* t- w; E/ [7 ^程序例:

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#include 8 ]& q; {( Z+ \' Z& V8 x#include 0 f' ^% g4 P* ~: |#include , k* S0 Q) t) R#include #include

int main(void) 0 t& T/ k0 l' z0 E8 m{ int handle; 6 R2 V9 a) k% e, h/ s; Mchar buf[11] = "0123456789";

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

if (handle == -1) printf("DUMMY.FIL already exists.\n"); - a/ s" Y4 \3 ?% Gelse * i$ j D0 }6 u& T2 Y{ printf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); 1 I: y0 r6 I% q; K7 r7 {8 f& Qclose(handle); } 9 B M2 Y0 g9 z3 [+ rreturn 0; } * y- r5 A5 h0 a1 c) @! ]

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函数名: creattemp ' {7 u$ w* d, L9 l! n功 能: 创建一个新文件或重写一个已存在的文件 & A% R# j4 t. D9 Q# W" V用 法: int creattemp(const char *filename, int attrib); - C( C( [8 t6 \" ]程序例:

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#include #include - Q: l$ U/ L5 x) H) ]( V' z#include

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

strcpy(pathname, "\\");

/* create a unique file in the root directory */ handle = creattemp(pathname, 0);

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printf("%s was the unique file created.\n", pathname); close(handle); 9 D6 L( i% v% |5 F, l x/ yreturn 0; 9 N9 k5 W- U0 |# m1 r} 6 V2 ]+ M7 F& x( R- U, H

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函数名: cscanf 功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); / S0 `" r6 k2 A% s程序例:

#include

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int main(void) 8 s v1 r6 F3 W{ ( D% w% L+ R$ u5 @/ [$ H9 e' p! cchar string[80];

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/* clear the screen */ + T: v, N: u d" `clrscr();

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

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/* read the input */ - f" [7 f9 L. Q( v9 Xcscanf("%s", string);

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/* display what was read */ * I8 D' @/ {, w& rcprintf("\r\nThe string entered is: %s", string); return 0; } 3 x! B) F8 g5 P" N. Z8 d 2 U- R+ [6 G8 L3 S7 H3 R) Q - @. I# ?. C8 X# P

函数名: ctime {0 {0 Q) d2 g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 & B0 R8 |0 @6 {# Q#include

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int main(void) & R3 J& _: k2 X) |9 \{ $ u4 }: D( m. m; D+ htime_t t;

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time(&t); printf("Today's date and time: %s\n", ctime(&t)); 8 @1 }# D9 ~( b% O' B- H! q+ w" u Zreturn 0; }

函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 ' F9 W. b$ { x! H7 r用 法: void ctrlbrk(*fptr)(void); 8 P* g* k. T" V K; h" t: m程序例:

#include #include

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#define ABORT 0

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int c_break(void) { printf("Control-Break pressed. Program aborting ...\n"); 3 m$ }( @2 Z4 o7 N9 Qreturn (ABORT); }

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int main(void) { ctrlbrk(c_break); 3 i& P* w0 `0 |$ |9 i) u- K9 h zfor(;;) { printf("Looping... Press to quit:\n"); } " c R) } c% B8 X, freturn 0; ! a( O2 M- I7 Y; T& K% |8 W}

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