函数大全(c开头)

韩冰

函数大全(c开头) 3 V4 o3 J. a, G( i* S4 U6 [7 r0 T" c7 C

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函数名: cabs ) l, b# w; m/ s7 }' t4 u+ p功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 4 ^/ {8 M1 q/ T* p) w程序例:

#include : I" m% x) ^+ [3 w. J# b#include

int main(void) { struct complex z; 1 O- c9 A K: J! e$ e0 @double val;

z.x = 2.0; * F" q) ~2 B9 u2 h. @5 g! T6 _z.y = 1.0; ) `- V( b3 L4 r' [# ?' F" W2 Eval = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); ! I0 W1 q2 z+ Yreturn 0; } ; E0 j- Q6 ?& U! f/ S5 A6 ]6 h 6 L8 B9 A# d. i& D- S* ~ : A. r+ f; S. N

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函数名: calloc 3 G& h$ `/ G% U2 `' X5 @7 i3 _. t功 能: 分配主存储器 , v7 [& P7 u; ~" M8 A用 法: void *calloc(size_t nelem, size_t elsize); ! x9 X5 Y# P" t! m程序例:

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#include #include

int main(void) : A6 M! s6 Y6 E{ char *str = NULL;

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/* allocate memory for string */ 6 `3 _, f. A G3 R- E1 Hstr = calloc(10, sizeof(char));

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/* copy "Hello" into string */ $ }" K/ `% S, Q G5 ^strcpy(str, "Hello");

/* display string */ 9 Q2 ?+ u( i7 b8 Eprintf("String is %s\n", str);

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/* free memory */ free(str);

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return 0; D. K- K7 E/ l) T) V} * { _/ C/ j ?! ]& E7 `; [ 9 P! Q' M' e! u1 ^, z# X

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函数名: ceil ) W0 D: a( z" ]8 M4 l功 能: 向上舍入 用 法: double ceil(double x); 程序例:

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#include #include

int main(void) 4 {% O- E' T: l" Q! s% _* S{ double number = 123.54; - @# m$ H& @1 X. f) rdouble down, up;

down = floor(number); 7 F5 `5 l7 k& c* W1 |" Fup = ceil(number);

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printf("original number %5.2lf\n", number); - h( j" u$ H, K3 a- `printf("number rounded down %5.2lf\n", down); printf("number rounded up %5.2lf\n", up);

return 0; , l5 r( d8 {7 O- Y# A; _} + z6 y) x ]& |9 l1 Y + O. W3 ?) ~4 f% p* J

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函数名: cgets 功 能: 从控制台读字符串 5 h6 t A0 \6 h用 法: char *cgets(char *str); ' E* p- T5 f/ R; [' N程序例:

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#include #include

int main(void) 3 r( N8 s4 Z& c4 ?4 Q{ F+ \) D( k: X+ p7 Rchar buffer[83]; ! _$ p8 R# g# ^char *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;

printf("Input some chars:"); * `& q$ Q& M# R& I( K y6 F Yp = cgets(buffer); 5 n3 g$ _4 R5 U8 f( h( ~' e0 oprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); " v# u' T L& k- i Fprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; , Z1 b8 x) v$ }" c9 y} 2 h) E! S" Z1 S+ i j / z$ M* u4 i1 S# g

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函数名: chdir 3 _. Y# Q. D% [; r) g4 n& E$ O7 |. H功 能: 改变工作目录 用 法: int chdir(const char *path); 1 ?3 o! s: ]" K, E程序例:

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#include 4 V9 r! ?3 r1 L ` s#include 4 V3 B6 \$ R! Z2 A U! _#include

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

int main(void) { if (getcurdir(0, old_dir)) 1 O3 j; [$ ]/ @& L) ~2 p{ - ?4 w& N; l6 Yperror("getcurdir()"); exit(1); 1 I2 z0 h! u G} printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) { * K: _) g. W# u) [8 U0 E# Y4 d1 fperror("chdir()"); " ]0 n% L8 s X- b! ^! mexit(1); 9 H2 _; H) y; o) E}

if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); } printf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); if (chdir(old_dir)) 4 O' k8 X) _1 ]+ f{ perror("chdir()"); exit(1); }

return 0; % N( }% V# Q$ `+ d1 A} ; H- h; x: ^. G; @' G% R

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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:

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#include # c' s8 y+ S+ q#include * Y: K: } {6 q- H#include

void make_read_only(char *filename);

int main(void) { / ^6 h2 E' F' I N$ e; x' cmake_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); $ ^* t8 s4 Y; H. k8 Q9 \6 }return 0; . O1 F: t: y/ Q7 P}

void make_read_only(char *filename) ' k6 v) l6 B, }% n0 l- y{ . f- {& Y- Q. m) U$ xint stat;

stat = chmod(filename, S_IREAD); 5 D# q) N- I/ k7 z2 Q4 b0 j: u Tif (stat) * n8 F2 ^* M3 v0 N8 p. l. ]printf("Couldn't make %s read-only\n", filename); else printf("Made %s read-only\n", filename); $ X' W8 W! \8 J# Z0 p; ?, e" X& o} ; p+ f7 V. Q' {8 [; t8 z9 r+ s

函数名: chsize $ A8 h+ L% ~0 x" ]: p1 d功 能: 改变文件大小 用 法: int chsize(int handle, long size); i# \6 \0 b- D- Z \程序例:

#include #include 9 ]/ J* V( D0 ]- q3 l#include

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int main(void) : J5 @* [6 w- |8 O" d{ ' h6 @; x Z$ p: wint 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 */ & m3 F5 K! _& W6 v& Vchsize(handle, 5);

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/* close the file */ close(handle); / J- u1 R# h: T9 s5 D0 O# Areturn 0; ' l! W# r2 c8 e. I" D5 {. k- E}

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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); , Q5 n" _4 S6 w8 d程序例:

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#include #include #include ' C; G9 T- x( n' V5 v D' f+ i#include

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int main(void) { 9 K! L$ z5 n! p# {8 Y/* request auto detection */ int gdriver = DETECT, gmode, errorcode; + M, {) \2 |6 N' S; O% q: |4 aint midx, midy; int radius = 100;

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/* initialize graphics and local variables */ - U* a6 ^! L1 G; L# v! K% I/ yinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ' g7 G. O+ h1 Nerrorcode = graphresult(); 6 {( k, a/ h& z' F* ~' Q) oif (errorcode != grOk) /* an error occurred */ 5 |! R H1 u& |$ Q& o" y% g$ l1 u7 z{ : \* D, i; S, V9 a$ w/ J/ Y; nprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); # O8 x8 Y& o3 ?3 Lgetch(); exit(1); /* terminate with an error code */ ( ~8 R% x7 e, a}

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

/* draw the circle */ ! z& u! B* Z/ m+ r) {: D; }circle(midx, midy, radius);

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/* clean up */ getch(); closegraph(); $ o8 o* c, b' Z* H7 ^return 0; " K6 f+ J3 r0 ]; O" T} # X/ K, N- L E2 |! v 5 k. c9 L( n9 d6 J% Q6 C: ?, m

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函数名: cleardevice & S+ q- Q6 W" |, ]5 t0 ]/ t8 N功 能: 清除图形屏幕 * H9 t8 W+ E/ s: F. F用 法: void far cleardevice(void); 程序例:

#include ' B* b+ V" _; h* Z9 n3 g#include #include #include

int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; 9 p' `1 ?) H) _int midx, midy;

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

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/* read result of initialization */ + }2 T/ H9 O) y5 Eerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { 5 D( {1 f7 q, G+ A- }printf("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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/* for centering screen messages */ settextjustify(CENTER_TEXT, CENTER_TEXT);

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/* 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();

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

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/* clean up */ ' i' `8 E. G) R9 k' Ngetch(); closegraph(); return 0; 8 Q/ A$ ^, T4 \- V. R} 1 U" t! @5 ~) \4 ?( `# J* P$ {3 y

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函数名: clearerr 功 能: 复位错误标志 - H0 C3 X U' i5 s用 法:void clearerr(FILE *stream); 6 w# f8 q" _( y2 j% m* r' Q程序例:

#include

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int main(void) { FILE *fp; ; k; y/ ?8 G0 _. U2 i: dchar 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); printf("%c\n",ch);

if (ferror(fp)) . _$ S6 g' {3 L{ / d* c! ]1 m" X6 p; |/* display an error message */ 0 d S1 \/ {! T) `: nprintf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ clearerr(fp); 2 [$ n; A7 L' C8 j- |$ ~}

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fclose(fp); return 0; ; I- G3 B0 \ j# [" m} 7 S# }* U2 y: P6 ?5 M $ V) s- ]; ]( i# m( v _7 U' Q

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函数名: clearviewport 7 k3 |! ^! c0 H& R: P* s" b功 能: 清除图形视区 D a6 k3 S& x+ Y+ H用 法: void far clearviewport(void); 程序例:

#include #include ) e; c' r- {5 w6 G#include #include

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

int main(void) { 0 f" @" [' i$ h. L) ~4 {* J: ^/* request auto detection */ int gdriver = DETECT, gmode, errorcode; % [9 Y4 Q8 y; e, e0 T& {int ht;

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

/* read result of initialization */ errorcode = graphresult(); # {: j! H/ |% k! Z) Qif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); $ C6 p! A& v7 Y3 D# }8 X H5 ]printf("Press any key to halt:"); 4 u8 a$ G! L# `( e- l: k0 V4 Dgetch(); . K' h8 r7 ?) Mexit(1); /* terminate with an error code */ }

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setcolor(getmaxcolor()); 2 V' V, P, Y2 e) _ht = textheight("W");

/* message in default full-screen viewport */ outtextxy(0, 0, "* <-- (0, 0) in default viewport");

/* create a smaller viewport */ setviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON);

/* display some messages */ , |3 U4 f2 e+ routtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 1 y8 \* E& i1 R# ~. `& Eouttextxy(0, 2*ht, "Press any key to clear viewport:");

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

/* clear the viewport */ clearviewport();

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/* output another message */ $ J& B/ z1 `2 o6 K8 C/ ~0 Houttextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); closegraph(); return 0; } + m! q( V1 S' v , U; W. s& w4 s# I$ c/ G7 ?; K 1 _! ~7 c1 s6 f: ?8 q4 p8 ^' g7 E

函数名: _close, close 功 能: 关闭文件句柄 6 O C3 q: t& d4 \- x用 法: int close(int handle); 程序例:

#include #include #include #include

main() 4 t# k+ e, k2 W( r) w& H& `{ - E! g/ ^7 Z/ d, I2 b! q- o7 Q/ fint handle; ) k9 @( i6 _7 l8 V z" k# l: {char buf[11] = "0123456789";

/* create a file containing 10 bytes */ 8 D+ b- t; W h$ i/ vhandle = open("NEW.FIL", O_CREAT); if (handle > -1) { write(handle, buf, strlen(buf));

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/* close the file */ . b: p a9 L4 `! M; C+ _close(handle); + b/ ]8 ~1 |4 S8 z; N+ Y3 @} 1 U' Q1 o2 |$ o& D. z4 R8 D& qelse " @1 k5 e* b: a- r4 A5 Y{ printf("Error opening file\n"); } return 0; 0 C! g- {* K0 X: w0 L}

函数名: clock D' U4 i6 c; y7 x* ^功 能: 确定处理器时间 用 法: clock_t clock(void); 7 }% e* _/ ~+ E8 m' S& `# d程序例:

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#include * B C2 Z; ?* b) z$ N#include 2 \. ~9 H- u$ j% g! y$ T3 v& j- b#include

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int main(void) { ; T" |1 q; A$ e9 K Lclock_t start, end; . S+ ?1 P4 K# S2 p& K9 O; Z8 fstart = clock();

delay(2000);

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

return 0; / u- s/ k7 w# B$ w* }" }. {3 J}

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函数名: closegraph 功 能: 关闭图形系统 # ^4 w) ?/ F# \8 p: x1 n用 法: void far closegraph(void); ! g1 ~" g1 b6 Q$ g: S) B程序例:

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#include #include #include ! P$ Y7 F0 F5 h2 {: S# L, }/ g. G#include

int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; 4 a5 e C& J/ n5 Gint x, y;

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

/* read result of initialization */ 3 m# T6 }/ L3 U9 G, ^errorcode = graphresult();

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if (errorcode != grOk) /* an error occurred */ * L4 K7 ?$ P9 d% u. }* y1 a% n7 v{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); + `/ Z7 E/ r( \0 `; m6 r1 u. s5 Y+ {' qprintf("Press any key to halt:"); . O# U4 Q$ F# g$ ~( egetch(); . }, f. ~5 K% X' F" p: Kexit(1); /* terminate with an error code */ }

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x = getmaxx() / 2; # } x5 _8 @4 U, w' O+ L/ Uy = getmaxy() / 2;

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/* output a message */ ' G, i! v- n* }; r6 j$ m: ~settextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

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/* wait for a key */ 7 L* S. F6 S9 ~- [, ~/ lgetch();

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/* closes down the graphics system */ * d6 m2 a( e4 u- lclosegraph();

printf("We're now back in text mode.\n"); 4 x7 P) b( W. m! y8 l: }printf("Press any key to halt:"); + H4 Y& E i, D3 Vgetch(); return 0; } - [ r4 h. ~. p/ ~+ N$ N: ~ / l- n* E0 p" y6 i3 q

函数名: clreol 功 能: 在文本窗口中清除字符到行末 2 p: P) a; p* O' ^用 法: void clreol(void); 程序例:

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#include

int main(void)

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{ clrscr(); # P9 `6 W$ |5 X+ T! |cprintf("The function CLREOL clears all characters from the\r\n"); cprintf("cursor position to the end of the line within the\r\n"); * a* l8 U+ T( p- Wcprintf("current text window, without moving the cursor.\r\n"); 2 a/ P* Y6 O) i: S. {9 Fcprintf("Press any key to continue . . ."); # c4 u2 y) I0 q! T5 S8 S9 U9 Y! xgotoxy(14, 4); getch();

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clreol(); ! D" p* ^ f. @/ u$ }* L( W( ggetch();

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return 0; 3 n) G9 e3 |* d+ U, N8 L' w" o+ m} % S7 Y8 A) n8 J& T ! F8 D$ B& T& G% N; n

函数名: clrscr * L: P F' s# ~! Q6 U, [功 能: 清除文本模式窗口 用 法: void clrscr(void); 程序例:

#include

int main(void) 9 V7 {% E4 F9 `3 J2 I{ " q+ }$ c6 T4 ?$ R8 tint i;

clrscr(); for (i = 0; i < 20; i++) 0 N6 J0 s! \' Ucprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); ) m$ m; c- V6 B# agetch();

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clrscr(); ( ~. B2 _ a gcprintf("The screen has been cleared!"); getch();

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return 0; + C- D& @' d) W7 {1 P} 7 G* I3 |* r: G8 y: y5 h ) v1 h: A, k4 S( H! s

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函数名: coreleft 7 g( f8 N; j- f功 能: 返回未使用内存的大小 ' F: Y7 Z- r7 j! a用 法: unsigned coreleft(void); 程序例:

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#include #include

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int main(void) { printf("The difference between the highest allocated block and\n"); ( ]% [ K% q% L" F8 jprintf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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return 0; }

函数名: cos 9 J9 d# z7 {+ j6 `功 能: 余弦函数 . `2 H( e* a' e! \( e6 z用 法: double cos(double x); 程序例:

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#include 4 S, l p- {% b$ q#include

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

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); % Y2 i- f/ h+ wreturn 0; 3 y$ s4 ]6 R( Y: p# }} 2 T3 y% y* a: C- C, k

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函数名: cosh 功 能: 双曲余弦函数 4 P6 n# K& Q7 y' }& u用 法: dluble cosh(double x); 1 \" y* p# `+ n# g" q* b程序例:

#include #include

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

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result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; } : g1 n; x6 B+ e / o$ M" p' ~$ {" K! b

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函数名: country . |% w7 Z) _, m3 ^2 N. F' x功 能: 返回与国家有关的信息 - O, q2 r$ `: W3 q, U" c用 法: struct COUNTRY *country(int countrycode, struct country *country); 3 F% l$ q: [2 c; p- Z& n程序例:

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#include ( ?5 p6 Y' A" b/ m5 s. R#include

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#define USA 0

int main(void) { * x6 i n" i" |% ` K7 ystruct COUNTRY country_info;

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country(USA, &country_info); 6 [ `9 E3 O' l. V* D, pprintf("The currency symbol for the USA is: %s\n", country_info.co_curr); return 0; 2 f$ X2 `5 Z, _+ w" l8 W9 T4 X3 o} 4 S8 w6 b: y, K E- u. Y

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函数名: cprintf 6 v" B3 T" `- O功 能: 送格式化输出至屏幕 # e7 g; ?' f9 J1 f- w4 b, |6 Q2 u用 法: int cprintf(const char *format[, argument, ...]); 程序例:

#include

int main(void) 0 W7 _4 y1 L% ?0 G: q{ /* clear the screen */ clrscr();

/* create a text window */ , @0 i. d/ Z/ K" Y L0 Xwindow(10, 10, 80, 25);

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

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/* wait for a key */ - z1 @" H( t6 Qgetch(); return 0; } 8 c3 d2 v8 f8 I) W( q $ w9 R& ^. g3 Q4 J! B

函数名: cputs 功 能: 写字符到屏幕 用 法: void cputs(const char *string); / ]% @6 X" O2 Z6 J程序例:

#include

int main(void) { /* clear the screen */ clrscr();

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/* create a text window */ 2 T9 k# T% y( O8 ewindow(10, 10, 80, 25);

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

/* wait for a key */ getch(); return 0; 2 \1 Q- ]" r- T; a& Q- F* m2 ~} * w% \2 {9 @- v% A

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 用 法: int creat (const char *filename, int permiss); 5 f5 v* x: g3 N程序例:

#include #include 3 T7 E, E2 L( k9 l- o#include , }" i" W2 H1 s, F) o#include

int main(void) ! V7 j9 j ?: N6 K% j{ int handle; char buf[11] = "0123456789";

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/* change the default file mode from text to binary */ 9 `; M- a" N, C" U1 N_fmode = O_BINARY;

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/* create a binary file for reading and writing */ + i4 T) B4 j) yhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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/* write 10 bytes to the file */ ) F+ J0 Q+ \5 X4 [* N! lwrite(handle, buf, strlen(buf));

/* close the file */ ( P5 K0 a3 \ B; v+ H( H H Jclose(handle); ) _) |) D7 i; j' J" V' {- Dreturn 0; } 9 Z6 [ ~- w- z3 B6 e

函数名: creatnew % C' ^8 X3 }2 c. E功 能: 创建一个新文件 用 法: int creatnew(const char *filename, int attrib); : o9 N! g/ F/ M: }程序例:

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#include . c4 `# U( w$ I' |. o+ F n#include #include * z1 l9 Z8 c8 Y" n5 l: n6 ?9 I#include ; a* a6 f5 X! {5 S2 T3 w. ~#include

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int main(void) $ r5 `- \( }0 q M{ int handle; char buf[11] = "0123456789";

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/* attempt to create a file that doesn't already exist */ , f& t, O: v0 [handle = creatnew("DUMMY.FIL", 0);

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if (handle == -1) : V, n l& X3 S0 {+ Xprintf("DUMMY.FIL already exists.\n"); else { printf("DUMMY.FIL successfully created.\n"); , ^4 Y% u& s, Z4 Jwrite(handle, buf, strlen(buf)); close(handle); } return 0; }

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函数名: creattemp / ~& D3 P5 ^% |0 e5 t9 ?功 能: 创建一个新文件或重写一个已存在的文件 " n5 n. b* E- W" ?% n8 F5 W用 法: int creattemp(const char *filename, int attrib); 7 v V8 T3 Y; I- U; v- z8 B程序例:

#include / P9 z# L$ g7 [5 b2 ^. A#include #include

int main(void) " U3 z9 g1 ^* j9 s3 `7 D{ int handle; char pathname[128];

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strcpy(pathname, "\\");

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

printf("%s was the unique file created.\n", pathname); close(handle); 4 T8 z0 _# E' D' ~% k7 S, vreturn 0; 2 C% e; f% ?' o' _- N( m9 G} , {1 q; @6 }0 _1 Y ( }/ Q% D) H" h& H% k1 F6 n3 Y

函数名: cscanf 功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); ! }9 P2 K5 I5 c& V3 q: K程序例:

#include

int main(void) { * n9 }5 `6 P8 ^- t0 j0 wchar string[80];

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/* clear the screen */ , \( t+ o. L5 M4 a$ s7 {clrscr();

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

/* read the input */ + m6 ]& U2 u7 u, Ycscanf("%s", string);

/* display what was read */ ! h6 ~/ n% H( [ M* ^cprintf("\r\nThe string entered is: %s", string); ; L m; m& \# g1 u* j7 ereturn 0; - `% I4 c4 B- j+ @) e$ I. p} 5 ]2 n, q" w V% D, E" Z 6 f$ h! M% h( {: K- N

函数名: ctime . w1 ~: C# T0 i, \5 v功 能: 把日期和时间转换为字符串 , v" D4 D4 O- h6 o5 [( E& M9 `用 法: char *ctime(const time_t *time); 7 |" ?7 k& K5 l- O$ m9 D+ d程序例:

#include #include

int main(void) { time_t t;

time(&t); : L" c! k% C2 {5 }& x: X# h1 mprintf("Today's date and time: %s\n", ctime(&t)); return 0; " T' t" K" S. c* W* X}

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函数名: ctrlbrk + y( A' D) O. _1 J功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); * h( n( w9 E4 e8 Q, ^程序例:

#include #include

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#define ABORT 0

int c_break(void) / P3 R2 |1 n$ e2 m3 A{ 1 K& n* w& C8 T6 nprintf("Control-Break pressed. Program aborting ...\n"); : n8 j" |+ U# S0 W! V5 hreturn (ABORT); |6 W7 c( x8 s$ V* q( ^9 a}

int main(void) { ctrlbrk(c_break); + R- F; M5 P# C4 t1 p ufor(;;) { printf("Looping... Press to quit:\n"); & b$ C% j! f9 `3 z} return 0; }

zjf

[em49]

谢谢啊

chenlk

有价值！

xxb1922

这样看太痛苦了，还不如去下载一个专门查函数的软件，我就有一个

xxb1922

这样看太痛苦了，还不如去下载一个专门查函数的软件，我就有一个

gssdzc

还是感谢分享。。。

hjl19890710hjl

特别感谢