函数大全(c开头)

韩冰

函数大全(c开头) ! a; P4 Y( a: h! T" b# C

函数名: cabs ; g0 B2 T, R) c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 1 G W0 a/ K; r, Y% A7 P3 t# ?. j#include

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int main(void) ' \( N" g! k6 L( B/ S4 @0 T{ struct complex z; 9 f- v- n. W8 Ldouble val;

z.x = 2.0; % o- L4 m: L8 h3 oz.y = 1.0; val = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); 4 _' [3 y6 O m7 j9 |& _, _3 v) \return 0; } 4 Q1 b/ S! p* l% o4 L

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函数名: calloc 功 能: 分配主存储器 2 a0 H, Q, o0 o: A用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include #include

int main(void) & k" g& O5 _5 ^& U+ b @4 I, `" Y{ . j3 e6 E( e1 fchar *str = NULL;

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/* allocate memory for string */ 3 j6 ^6 D% |4 j {, A$ c: W6 d' q$ ~$ r _str = calloc(10, sizeof(char));

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/* copy "Hello" into string */ 4 r' D( D, @1 u. E& w W& Kstrcpy(str, "Hello");

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

/* free memory */ free(str);

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return 0; } 9 x8 b9 N7 W. b' W ! A( D) p2 s$ H" X

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函数名: ceil 3 B* _7 x0 k8 A$ N; M3 V2 C功 能: 向上舍入 2 t' h0 v, a$ l7 U* e) C用 法: double ceil(double x); 程序例:

#include 2 l5 B& f: ?$ W/ f. J#include

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int main(void) { double 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); ; I. i+ r; K: K1 Hprintf("number rounded up %5.2lf\n", up);

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return 0; } " q* `3 s3 Z* Y: W/ p" Q1 x7 Q . H% B+ ]* G% x

函数名: cgets 5 y" l U( ^. v9 k% q1 Q2 Z: Y功 能: 从控制台读字符串 用 法: char *cgets(char *str); 2 L- i% [3 P2 T/ v6 X) J程序例:

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#include r* p# X* v% n) {8 L#include

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int main(void) 1 a Z, C) n" `{ ( L$ b d7 p$ S/ l$ Lchar buffer[83]; U* G* i( ?$ [2 v0 rchar *p;

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/* There's space for 80 characters plus the NULL terminator */ D5 a8 `) _5 Gbuffer[0] = 81;

printf("Input some chars:"); 3 T ~4 Q) U/ \p = cgets(buffer); 9 l$ Y) T/ F0 D0 t `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 */ buffer[0] = 6;

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printf("Input some chars:"); 7 m' X( K9 e, f a3 tp = 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); 2 D. C9 _# e, d0 ]return 0; ' U$ G! j6 C: e6 K* P$ X$ _8 w} - O z) x) ^& [0 H! Z

函数名: chdir 功 能: 改变工作目录 ) N/ O4 t( I: l6 r2 w5 h, Z用 法: int chdir(const char *path); 程序例:

#include #include #include

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char old_dir[MAXDIR]; * a* k% e2 U% }; A9 P# Hchar new_dir[MAXDIR];

int main(void) { if (getcurdir(0, old_dir)) 9 [& I( E4 D- L3 p/ Z8 Q" Q{ perror("getcurdir()"); exit(1); - ]* r) S: }% D* k P0 M} printf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) 1 I. `8 b5 v; E0 E. H( L{ 7 |6 H2 l7 }9 eperror("chdir()"); }& v% j; S$ P6 W4 ?4 C) Vexit(1); }

if (getcurdir(0, new_dir)) ' R0 }1 W9 e- w% ?6 k{ perror("getcurdir()"); / H2 R% Q0 p' o* bexit(1); & Z! _( \+ j! e} printf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); & B' L6 v8 H# cif (chdir(old_dir)) & n, o2 D5 e) E, q1 s{ ' }# I' r& I' b: ~# W# Bperror("chdir()"); exit(1); % j3 o" D$ o* `5 t; Y9 t& d z/ l}

return 0; 3 y( `2 f7 b) w* z) y} $ W3 b- C" y& F: I& ]( X2 ]( O

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函数名: _chmod, chmod 7 k! D: R% Y8 ^8 O6 p) {$ L. [功 能: 改变文件的访问方式 , F+ S0 m c+ i$ h用 法: int chmod(const char *filename, int permiss); 4 a# F1 {1 B) ~# ^程序例:

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#include #include 5 s" i- z' d3 X0 Z#include

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void make_read_only(char *filename);

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int main(void) ) N0 r$ I$ D, Y/ r8 ]{ # e$ I5 @5 L4 J( Y% J* F- U9 ]make_read_only("NOTEXIST.FIL"); / R8 B" r1 N+ ?- I1 P; vmake_read_only("MYFILE.FIL"); h, v% ?! ?6 @7 m4 Mreturn 0; 7 }( z2 j( I0 _: q# r0 N}

void make_read_only(char *filename) { t/ }2 S, U1 B9 D. t) tint stat;

stat = chmod(filename, S_IREAD); % r2 b6 N: D n& pif (stat) printf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); } 2 |4 e: k' @( l * Y) Q( ]. U4 g" {4 X0 g: L' D" I ; _& Z; X( g' t* h0 ?- t. E

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函数名: chsize 功 能: 改变文件大小 ! P0 V& s$ M3 }6 @用 法: int chsize(int handle, long size); 程序例:

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#include : A5 t i0 @; ?! ?$ q6 l8 D- J: f#include #include

int main(void) { int handle; char buf[11] = "0123456789";

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

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

/* close the file */ close(handle); 6 h# @0 x+ H5 P0 E0 Y1 lreturn 0; } ; X/ W8 E% K# j$ W

函数名: circle 4 {; Z. u- F+ S) @ A9 e功 能: 在给定半径以(x, y)为圆心画圆 $ _1 p0 j" n" Z1 J$ Z. ^用 法: void far circle(int x, int y, int radius); 程序例:

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#include K' D' U8 w/ X#include " M" i* b. @& B' W#include ! g% t& x ^5 m% ]+ G3 s3 F( l* T#include

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int main(void) { /* request auto detection */ 7 J, x' I& n; P: y/ iint gdriver = DETECT, gmode, errorcode; int midx, midy; ' @/ e$ P5 x( F2 oint radius = 100;

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

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/* read result of initialization */ errorcode = graphresult(); ( E$ |# ^/ M+ K! Y6 rif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 S$ p! `1 m: X! d, N$ ]$ X1 A7 pprintf("Press any key to halt:"); getch(); # j# |( W$ P, {! S/ bexit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; " |; c4 l0 Q% n9 \midy = getmaxy() / 2; . Y- J# p* V+ W( i, T4 y0 Tsetcolor(getmaxcolor());

/* draw the circle */ 9 p. j% {" t4 U. _% ~( M) j. J* fcircle(midx, midy, radius);

/* clean up */ . \, P) a4 ~( B* hgetch(); % @( e3 `8 ^* v; Eclosegraph(); 0 ]% h# D/ v. U; qreturn 0; + O) @, o) g( `0 u, p} 3 \9 a N$ e8 ^" Z, \

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函数名: cleardevice 功 能: 清除图形屏幕 - K7 U- z& P7 e9 e9 `' L. |# L用 法: void far cleardevice(void); 程序例:

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#include ( e/ H6 A0 e; G9 D! D$ v#include #include #include

int main(void) { /* request auto detection */ 6 Q" b/ n* b8 R4 Z7 q7 C# k0 Cint 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 */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ $ n. t% E# ?- W8 O4 C- R; T{ / l2 \( d9 y: t: C E! u/ nprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ ! W* Z1 A& ]# z8 k8 S}

midx = getmaxx() / 2; 8 v! K% m9 K7 P- Cmidy = getmaxy() / 2; setcolor(getmaxcolor());

/* for centering screen messages */ b+ q: v2 X8 ?3 W8 x9 ]" \settextjustify(CENTER_TEXT, CENTER_TEXT);

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/* output a message to the screen */ + W& w; ]- }- H2 u/ Mouttextxy(midx, midy, "press any key to clear the screen:");

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

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/* clear the screen */ cleardevice();

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/* output another message */ 1 }4 f- o6 V) l- z' N- X1 Aouttextxy(midx, midy, "press any key to quit:");

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/* clean up */ getch(); closegraph(); return 0; 6 ~5 p' \# j* E% |" ~5 j} ( ?5 Z1 ^6 b9 _1 ?; Y* k0 V* x2 v/ c - `$ e; [$ A% `$ Q2 |- J. A

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函数名: clearerr 功 能: 复位错误标志 用 法:void clearerr(FILE *stream); 程序例:

#include

int main(void) 8 f; g3 z5 g) r) l0 g) k9 \{ 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); ' L) C5 t" A) c8 N% [( U4 w" @printf("%c\n",ch);

if (ferror(fp)) . Q! ]* }1 _3 }9 V{ : c0 r& ^9 I" f2 o. m4 Y/* display an error message */ printf("Error reading from DUMMY.FIL\n");

/* reset the error and EOF indicators */ 5 k6 T5 R+ i3 d, H0 iclearerr(fp); }

fclose(fp); : e; O$ J7 n0 P r1 vreturn 0; ) z L, J( U; G& J5 _5 U} + |7 A8 a& \+ B9 O - J6 F( C# A/ \/ c

函数名: clearviewport ; c5 b- X, M" j+ l( ]" ~+ ^功 能: 清除图形视区 0 o+ j2 @4 @ ?4 A$ Q% `+ T用 法: void far clearviewport(void); ; R; T# N) n) Q% N; K! T% d程序例:

#include 7 \$ {; P1 r3 V/ C#include ' q% f" B; T6 @4 z* A#include 2 f. Y$ s# q1 P0 u9 h& J/ X#include

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

int main(void) k5 w5 M: _+ C% f- q+ U{ / v; q$ Q( t% l/* request auto detection */ # I& L6 P( L$ l( l- |: @/ nint gdriver = DETECT, gmode, errorcode; int ht;

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/* initialize graphics and local variables */ : i) o' b' p: l$ _; R" ainitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ; k* h- [$ N9 a- [- R& werrorcode = graphresult(); . V, l: A6 b, y0 `if (errorcode != grOk) /* an error occurred */ j6 ]1 @0 p- G, }; A{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); + X9 ?! |$ V" T& Fprintf("Press any key to halt:"); 1 u5 a- t) \( i6 R1 e. V7 I4 p+ E" z6 mgetch(); exit(1); /* terminate with an error code */ + ]4 \- ?7 o9 D! ?( Y9 a}

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

/* message in default full-screen viewport */ % |. v3 J M2 P; l0 A) S Mouttextxy(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 */ $ a0 v# u) q2 C6 R4 W5 iouttextxy(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 */ 2 u5 u: i0 Y$ A ] Z1 `clearviewport();

/* output another message */ ) F9 G" a( O# f- _( l! jouttextxy(0, 0, "Press any key to quit:");

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/* clean up */ getch(); closegraph(); * C. s8 j( S* M; u2 d# Nreturn 0; 9 o/ H* Y, h; z- L5 f} - y% i+ Y9 s" G" A7 A ; }. l$ \7 f" _4 r0 l3 g

函数名: _close, close 9 k& ^; u3 f0 k2 w功 能: 关闭文件句柄 % S" u0 _' b+ |& j \用 法: int close(int handle); 0 [3 V/ z- Z/ k/ ]* s) F程序例:

#include 5 U1 \: d) K S% \, m+ O. J7 j/ i#include #include #include

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main() { ! G- n0 O4 [) H2 M1 l5 Eint handle; char buf[11] = "0123456789";

/* create a file containing 10 bytes */ ) w, x* f( h1 d) hhandle = open("NEW.FIL", O_CREAT); 6 u4 ?" j# c7 S y+ ]( ?) c' Dif (handle > -1) 3 ]4 F- V4 V' J6 D* w{ write(handle, buf, strlen(buf));

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/* close the file */ % b6 J9 d B; q( |6 bclose(handle); + R8 Y' Y4 A2 f3 x} . }& {0 D; H, telse { printf("Error opening file\n"); } return 0; * h8 t- x* k0 ~: `6 H, b} & \4 @% |: O- n , z6 b3 @! s- p8 Y( `

函数名: clock 功 能: 确定处理器时间 用 法: clock_t clock(void); + F9 Q0 k" I0 i程序例:

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#include + `3 P( }( [' Y7 p8 S, [' |#include #include

int main(void) { 3 c+ z$ C. E0 t$ E0 L$ i3 B! qclock_t start, end; start = clock();

delay(2000);

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

return 0; }

函数名: closegraph 功 能: 关闭图形系统 用 法: void far closegraph(void); * T) q# B0 o# }+ d$ g程序例:

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#include #include ' _2 b" j& l. \. O' w#include #include

int main(void) 8 O: I# y m& W6 J{ 4 p4 K3 n) h1 H& Y/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int x, y;

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

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

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if (errorcode != grOk) /* an error ' D* ^/ g5 I' n/ foccurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); $ e! _8 j5 ]: Z" }' dprintf("Press any key to halt:"); : q! L8 g' l5 j6 H+ R jgetch(); exit(1); /* terminate with an error code */ }

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x = getmaxx() / 2; ) d" ~' ~* C u% J" S. L% t* {7 Ty = getmaxy() / 2;

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); + N7 h8 R/ }+ A3 g, Qouttextxy(x, y, "Press a key to close the graphics system:");

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/* wait for a key */ 3 I$ @& E, I1 Y' C9 Wgetch();

/* closes down the graphics system */ , P' {+ c: U# T! l0 ~; }closegraph();

printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); E8 d: u5 k, V# Kreturn 0; } 9 W8 p( \: x7 L* D. Q% ?# K . p' N* E. y9 B) z) @, U

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函数名: clreol 功 能: 在文本窗口中清除字符到行末 % }" I$ {) V0 F9 G8 d用 法: void clreol(void); ! z1 | m8 k% |7 Y9 u3 o) \程序例:

#include

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int main(void)

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{ ; Z5 i, d% q, l, z; jclrscr(); cprintf("The function CLREOL clears all characters from the\r\n"); cprintf("cursor position to the end of the line within the\r\n"); cprintf("current text window, without moving the cursor.\r\n"); ) X" y# d: T, T6 L" M& gcprintf("Press any key to continue . . ."); : l1 J% ?& h& m, zgotoxy(14, 4); $ Y9 F, Q, L8 t! |8 r. V9 fgetch();

clreol(); getch();

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return 0; 6 h( o2 V& `" ]+ W, L} 8 b% L- @6 q4 b$ J' k1 B

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函数名: clrscr 8 u' h$ }: r: Y6 A5 Q, h o功 能: 清除文本模式窗口 ' P4 G, n# N5 [" V9 B用 法: void clrscr(void); 程序例:

#include

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int main(void) { int i;

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clrscr(); for (i = 0; i < 20; i++) , {& d$ h% L# V* ~5 hcprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

clrscr(); % r$ j1 P( `8 U1 m3 z8 vcprintf("The screen has been cleared!"); getch();

return 0; }

函数名: coreleft 0 G h8 f; y( y/ |2 }" a) U功 能: 返回未使用内存的大小 " l3 _; D2 {! @" m用 法: unsigned coreleft(void); 1 i1 Y+ [2 s, ]6 l4 p/ h- b程序例:

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#include #include

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int main(void) { ( p+ h" W+ D; e/ ]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; 8 y6 D4 x6 o6 V! B. c6 a- a} # G* A" J1 U0 L7 t

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函数名: cos ; _# N/ Y( W: o7 Y- d功 能: 余弦函数 * j; @1 G; B$ t用 法: double cos(double x); 4 d- |: F+ b9 p5 g) l5 l8 ]7 k! y程序例:

#include 2 U) Y( |4 B$ r& o#include

int main(void) & [3 o4 J0 D! i7 i{ 2 M$ T! [3 p6 i2 B& ]double result; double x = 0.5;

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result = cos(x); 8 g0 |# D2 [5 S/ e, ?" A. ~printf("The cosine of %lf is %lf\n", x, result); 8 U8 p* E* n+ L u1 `' nreturn 0; } 2 G/ \+ l6 G7 k/ {9 O

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函数名: cosh & j/ P( e- C0 J2 D8 ^' Y4 v6 u5 }功 能: 双曲余弦函数 ) F1 _, c% ~. z0 h用 法: dluble cosh(double x); 8 F/ R6 S# \, K. Y程序例:

#include & m" i* }0 i- j8 _# _# @#include

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

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result = cosh(x); 8 q s) f7 R' S, O# t8 s8 x* x7 Fprintf("The hyperboic cosine of %lf is %lf\n", x, result); 3 h Q4 s0 H2 G! h6 Creturn 0; } 7 z& H$ z4 H7 P $ P2 J/ T% @1 h9 u0 I6 P

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函数名: country Q+ P# B i; d功 能: 返回与国家有关的信息 用 法: struct COUNTRY *country(int countrycode, struct country *country); 程序例:

#include + @+ }0 d) P- }$ O0 Y* o: E1 l#include

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#define USA 0

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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", ( z- z2 ^0 A" u, N3 K ?country_info.co_curr); # W- s" A, r6 F! ^return 0; } + _( r U9 k, l3 m . }! w. r: S+ H

函数名: cprintf 功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); 程序例:

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#include

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int main(void) { /* clear the screen */ H0 k: @% M9 {: [$ u b aclrscr();

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

/* output some text in the window */ : B V- Z2 H, j5 Q* @# Rcprintf("Hello world\r\n");

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/* wait for a key */ . y! W* M8 q9 R% A, G/ Igetch(); return 0; b: J }/ A$ {/ t: o: D: [8 K} ' i* d, Z. J' `( J- E 3 L' i) `2 S. y

函数名: cputs 功 能: 写字符到屏幕 9 D9 M3 d) ^% ]/ p( b" R8 A用 法: void cputs(const char *string); ( O; p7 p2 c8 e( M程序例:

#include

int main(void) + M1 j G' q; Q* F7 g{ /* clear the screen */ clrscr();

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

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/* output some text in the window */ 8 _& y4 Q% y! `- X9 Scputs("This is within the window\r\n");

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/* wait for a key */ ( I: T1 A# f6 h: S1 d- B) Y: Qgetch(); . G, }4 d6 U5 Sreturn 0; 3 f& o& D8 ^+ ~} 2 P7 ~6 Q9 [* [' E6 b1 Z; M& M& F 1 C# R5 \$ P- j: o) P

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函数名: _creat creat + X" t3 O' ]$ z% ~3 a功 能: 创建一个新文件或重写一个已存在的文件 . p" i9 B2 T9 z" ~1 p( O# _用 法: int creat (const char *filename, int permiss); g a1 N5 o5 N4 G# {) r程序例:

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#include #include #include 6 ]/ l8 S/ N% ?2 b#include

int main(void) { 5 ], ^4 j- W& U6 W$ W" Hint handle; char buf[11] = "0123456789";

/* change the default file mode from text to binary */ _fmode = O_BINARY;

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

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/* write 10 bytes to the file */ % E/ @! n+ d3 B" B3 wwrite(handle, buf, strlen(buf));

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/* close the file */ close(handle); 1 V8 G8 v1 ^: c- I' ~return 0; : A3 r' ?3 {+ n; p4 @}

函数名: creatnew 1 u) K# Y/ H& F功 能: 创建一个新文件 / Z$ ? x3 V0 Z% D2 D用 法: int creatnew(const char *filename, int attrib); 程序例:

#include ) s5 q& y g5 ^ T* _- e#include 9 p/ N A! Y' d) F#include 7 ]: z4 @! f! m j& t% z#include #include

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int main(void) 6 C; E1 n) j- f9 Z{ int handle; : i( i5 O! j' k$ ^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) ' w9 b" ]1 O1 Y5 u+ D2 sprintf("DUMMY.FIL already exists.\n"); % t/ p# n6 W7 B. Q2 Y' ?else ) N* }! g! C3 S) s5 y& w, ?$ S{ 2 U* L R( r! l0 i7 J1 Gprintf("DUMMY.FIL successfully created.\n"); & k8 ^) {, I: G$ kwrite(handle, buf, strlen(buf)); close(handle); } ' S3 b b& x0 y Kreturn 0; , X) r: j' }. I1 ]$ W} 6 J O5 F3 v- Z3 _/ ` - v3 ?& g% A# T3 v4 P. u F" D / \' Y( }7 e/ h

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函数名: creattemp # K S. }4 S' |5 x9 f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); 9 Z( B, s4 b1 b7 v8 d5 p# i+ @) j" w程序例:

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#include #include 6 }& f# q+ ]5 G6 N#include

int main(void) 0 X6 C3 x; N& `* p9 S+ g{ int handle; 7 y& s/ a. _3 j8 ~9 s- ~4 ]char pathname[128];

strcpy(pathname, "\\");

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

printf("%s was the unique file created.\n", pathname); close(handle); ! W$ O" y5 \4 t, {return 0; ) Y% I( u# g# b. f} + {3 {! j: B( Z" K: E! U' x ! q3 j4 R; `9 n. G " c+ [, P4 |/ ~) M# _- C

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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, ...]); 程序例:

#include

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int main(void) / c( g- l+ v" _' Z7 D% X{ char string[80];

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/* clear the screen */ clrscr();

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/* Prompt the user for input */ 1 U5 ?' o6 a4 I! h0 G4 l, ?6 |cprintf("Enter a string with no spaces:");

/* read the input */ / `8 A O6 z! d a; j% _5 ^cscanf("%s", string);

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/* display what was read */ # V6 \9 L5 }( w5 ^4 T2 y3 k9 pcprintf("\r\nThe string entered is: %s", string); 0 G { [) {4 F& D. _9 Mreturn 0; 8 E% U5 ~9 Q' D6 t% I. J" M} 1 I# i X- z1 B) i0 S8 `6 X/ @$ n

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函数名: ctime 功 能: 把日期和时间转换为字符串 用 法: char *ctime(const time_t *time); & d8 Y; O- A# A# ^程序例:

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#include #include

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int main(void) { time_t t;

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time(&t); printf("Today's date and time: %s\n", ctime(&t)); return 0; 8 w8 E d2 ~* s! ?# r} ) k) p! K; W& R. S

函数名: ctrlbrk 2 l" V, |% x" x8 m2 n功 能: 设置Ctrl-Break处理程序 7 ~7 D& j; q' G! G) p; z8 m用 法: void ctrlbrk(*fptr)(void); / p* H8 @8 b8 I5 S程序例:

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#include #include

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#define ABORT 0

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int c_break(void) { printf("Control-Break pressed. Program aborting ...\n"); 1 M2 `( n+ Y2 g* wreturn (ABORT); }

int main(void) { ctrlbrk(c_break); 5 m6 v6 f/ `: ?$ S% P6 q9 Ofor(;;) W7 z1 U& L$ `0 g0 ]% Y% a( d{ printf("Looping... Press to quit:\n"); } ' \( d& h$ W+ k3 m b0 m* V, w" r- sreturn 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