函数大全(c开头)

韩冰

函数大全(c开头)

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函数名: cabs 功 能: 计算复数的绝对值 0 z2 _2 @: D8 u$ H, k/ X) f L用 法: double cabs(struct complex z); 0 O% ^' b0 j$ F7 [程序例:

#include #include

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int main(void) { struct complex z; double val;

z.x = 2.0; z.y = 1.0; 4 V7 h) h0 D% c5 L: Y- Pval = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; } 3 c; T q& i9 X, v* | " ^- I7 }0 g1 s6 K+ m1 y

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函数名: calloc 功 能: 分配主存储器 用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include ( M% ]2 @0 r2 v. y2 p' z I3 z#include

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int main(void) 1 O9 v0 o& D6 k8 ~+ i% }9 {$ V{ + w% S; G) r9 O6 Achar *str = NULL;

/* allocate memory for string */ 7 l) F5 B! M4 e6 nstr = calloc(10, sizeof(char));

/* copy "Hello" into string */ 9 x6 r: p* j' `) Zstrcpy(str, "Hello");

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

/* free memory */ 5 J0 g" ?+ j$ _9 A- P5 yfree(str);

return 0; / F$ X0 @0 m I: F} 6 n/ j0 i- z1 g' g

函数名: ceil 功 能: 向上舍入 6 y. I% |# ]) u1 U! u用 法: double ceil(double x); 程序例:

#include % Q& V2 C2 A% C#include

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int main(void) ! T5 w: s; V2 N0 Z( v{ double number = 123.54; - L2 d+ F. P6 {. t! V X3 `6 i- ^double down, up;

down = floor(number); up = ceil(number);

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printf("original number %5.2lf\n", number); printf("number rounded down %5.2lf\n", down); printf("number rounded up %5.2lf\n", up);

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return 0; ; s+ ]9 D3 h; t6 P. R} 0 T O: G/ z. E: E

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函数名: cgets : p3 l' D% _" P5 @7 d7 z1 \4 ^功 能: 从控制台读字符串 用 法: char *cgets(char *str); & Q# v- F; X: W2 P! w程序例:

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#include #include

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int main(void) 4 q! O/ k T1 G- B" D{ char buffer[83]; 7 m G" ^7 X" W. P; kchar *p;

/* There's space for 80 characters plus the NULL terminator */ 4 E1 q8 x; I& p9 m2 q, \buffer[0] = 81;

printf("Input some chars:"); ( `! L+ a7 w. Gp = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 5 |' P% H0 _9 u$ N4 qprintf("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 */ # z0 z+ `# y0 ?buffer[0] = 6;

printf("Input some chars:"); p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); ' ~4 G% P- G8 m0 F2 ~' Q6 Bprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; } , ?- o6 L3 D( e1 C4 R3 O * [, A+ P' P) F" a8 I2 d* u( x4 k

函数名: chdir 功 能: 改变工作目录 / o0 w! a% r) v, R$ ^% n! c1 Q用 法: int chdir(const char *path); 程序例:

#include #include " @+ v$ V3 |8 J#include

char old_dir[MAXDIR]; 9 h" C, }% _) t9 Xchar new_dir[MAXDIR];

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int main(void) 3 W I Z H) f# Y& P; x{ if (getcurdir(0, old_dir)) { 4 N5 ~0 U6 V4 J% m$ P* U7 H" H Cperror("getcurdir()"); : M# r: C* `) j4 G nexit(1); } 0 |$ e8 c4 i8 A. N( Bprintf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) { perror("chdir()"); exit(1); : J5 \& n# _5 U5 |/ o3 c+ ^/ P}

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if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); 5 P. d) x1 ^. b" `( w& X} printf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); if (chdir(old_dir)) { ! J' }0 \$ t2 M3 A* Sperror("chdir()"); exit(1); . t% E9 s; d- n; F}

return 0; 8 p. K4 g1 a1 h. _' s} / |8 Q$ Y) ~& [% I6 ] & p. W& l1 z4 z. Q, b8 C- e

函数名: _chmod, chmod s0 C1 y; g, m$ s功 能: 改变文件的访问方式 ; d, l5 m/ Y7 h2 \用 法: int chmod(const char *filename, int permiss); ' B' Y- w* e! i8 U* a( ^: m程序例:

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#include ( f( ^3 ?% o- j6 I2 S#include #include

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void make_read_only(char *filename);

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int main(void) : H- [/ H& `8 |+ V8 h{ make_read_only("NOTEXIST.FIL"); make_read_only("MYFILE.FIL"); return 0; }

void make_read_only(char *filename) { int stat;

stat = chmod(filename, S_IREAD); 1 n, q8 y2 m1 Oif (stat) # C" F) @% k! b% n& Z4 F& C' pprintf("Couldn't make %s read-only\n", filename); else $ r; g: K0 F9 | \' Zprintf("Made %s read-only\n", filename); }

函数名: chsize 7 ^- v4 N0 g* e! E {功 能: 改变文件大小 6 Y- Q) t4 R" p用 法: int chsize(int handle, long size); 程序例:

#include , M. s' }( D9 S, X#include #include

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int main(void) . L9 G, }/ g+ }! X4 q" T' I{ int handle; 9 @" U. l9 J. q8 zchar buf[11] = "0123456789";

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/* create text file containing 10 bytes */ ( y" V( M" v3 I2 }" a9 L zhandle = open("DUMMY.FIL", O_CREAT); , ^- C+ i1 B1 f, a) R7 D% k) Gwrite(handle, buf, strlen(buf));

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

/* close the file */ 2 e/ N" W9 o" @; |( L$ N+ kclose(handle); return 0; ' D1 b2 c7 b& S" q4 \5 a} ' x, [0 D" e) A! _8 p E! w, ?0 [

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函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 " e2 }% H% w4 K& ]& x用 法: void far circle(int x, int y, int radius); 8 ^' p9 L1 e' ?程序例:

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#include - E9 C5 M1 t/ x, U) a#include & l3 D5 V# n6 H#include #include

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int main(void) { 4 c1 {7 }. G8 W' `/* request auto detection */ $ X9 D% g& l6 u4 B/ C8 W# qint gdriver = DETECT, gmode, errorcode; $ E. G. r3 h) [% v$ ~5 u8 X: `int midx, midy; int radius = 100;

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/* initialize graphics and local variables */ 1 T4 Z" {+ [' e" y3 _) Iinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); 7 h8 x \2 ~; m) \if (errorcode != grOk) /* an error occurred */ - u6 c0 E+ L. T- k{ + }- _$ u+ k6 Y$ O/ D* ^; iprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); ) ]& ?+ p$ G2 U: j4 U. K6 lexit(1); /* terminate with an error code */ 1 k' `: B* ^! O$ G}

midx = getmaxx() / 2; midy = getmaxy() / 2; 2 I1 h$ I) ~1 _# D: Tsetcolor(getmaxcolor());

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

/* clean up */ getch(); + _6 v6 m2 [3 bclosegraph(); return 0; } 7 [1 I4 M' H" m2 T# k) w- b

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

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#include : s6 `( ~9 i/ u5 k#include #include #include

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int main(void) . F. s' _6 U Z4 B$ d* t9 [{ + v. X* s5 M/ z& Q/* request auto detection */ 1 E. @" a# F& E9 A1 ~int gdriver = DETECT, gmode, errorcode; * }) v) H$ p' q9 e; H, E+ T/ A F3 vint midx, midy;

/* initialize graphics and local variables */ 9 r! y1 ~4 a0 Hinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); - b- ?+ `7 e. c* {; n! r2 Uprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ " s4 C) c g" B) S4 k2 L n0 G}

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midx = getmaxx() / 2; midy = getmaxy() / 2; # g7 I6 |" P B" a8 |2 {setcolor(getmaxcolor());

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/* for centering screen messages */ : E) v* z' e! x# z5 S. L5 r4 asettextjustify(CENTER_TEXT, CENTER_TEXT);

/* output a message to the screen */ b5 y& ?0 E' j7 X1 z: p+ t7 eouttextxy(midx, midy, "press any key to clear the screen:");

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

/* clear the screen */ cleardevice();

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

/* clean up */ getch(); closegraph(); I( Z9 c) v/ O2 s$ O8 X5 Ireturn 0; } : C9 _' @ S6 S( E# F 4 W( D! X- }: B7 u& g

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函数名: clearerr 功 能: 复位错误标志 ; L# Q( p# Z6 ]用 法:void clearerr(FILE *stream); 程序例:

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#include

int main(void) 8 b; X* ]8 D8 r! {{ 7 Q3 U; v0 H3 f) R/ R( ZFILE *fp; + m- Y6 ?5 r# p0 l5 gchar ch;

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

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/* force an error condition by attempting to read */ " A1 |* ]) F0 ^# N( N2 |/ d4 ych = fgetc(fp); " j1 `& f( q" m- Z3 Y2 mprintf("%c\n",ch);

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

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

fclose(fp); 5 S2 } m9 v/ |; `8 greturn 0; f, q6 h1 [- h! d6 ^; W, w} $ U; Z# ~+ J4 \5 Y

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函数名: clearviewport ! P* v6 H' A; b0 ?6 a! d功 能: 清除图形视区 3 \1 c# M3 z. V用 法: void far clearviewport(void); ; B- j1 C' @% |3 N3 r6 \% V, b程序例:

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#include / \7 D: ~- |' I" ^; S#include 0 s4 `, |: a* f. s0 w#include ( I9 y# s5 L7 y5 J; c& T#include

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

int main(void) 7 I7 @9 w0 V" q7 h, m( @{ /* request auto detection */ int gdriver = DETECT, gmode, errorcode; }' a, D. n# d4 T) Y0 Dint ht;

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/* initialize graphics and local variables */ * M1 u4 _, F) l( g' s: _initgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); ; y( Q5 V! A0 N0 h* i* @4 Vif (errorcode != grOk) /* an error occurred */ { + s9 \- n+ j+ m- w, lprintf("Graphics error: %s\n", grapherrormsg(errorcode)); & V; x8 P4 V# p# @; o- R$ Vprintf("Press any key to halt:"); - X! r2 Q# A* n) y ^- Qgetch(); exit(1); /* terminate with an error code */ + ~' `/ L/ f- |+ ?( p3 L$ I}

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

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/* message in default full-screen viewport */ ) P9 W" f! T* e" L I0 uouttextxy(0, 0, "* <-- (0, 0) in default viewport");

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

/* display some messages */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); " D5 @* }9 o' s, Iouttextxy(0, 2*ht, "Press any key to clear viewport:");

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

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/* clear the viewport */ clearviewport();

/* output another message */ 2 X$ m4 D+ n$ f) Louttextxy(0, 0, "Press any key to quit:");

/* clean up */ ; y5 b7 @9 H' s5 p/ c8 qgetch(); + C+ j8 z/ D+ D# Uclosegraph(); return 0; } 7 G C h( V/ o F& z+ J

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函数名: _close, close 功 能: 关闭文件句柄 / w+ B9 G& L2 w$ \/ ?( M. Y用 法: int close(int handle); " B6 Y! N) h- r程序例:

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#include 3 p" u3 R o O V. N* ~$ }1 p#include 0 K, b2 l1 ]. d+ M" ?- Q' {. M#include # Y# e. ?' m: S P. c) g$ A#include

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main() { : z& y, Z" [7 l- iint handle; 5 h( s n* O7 Tchar buf[11] = "0123456789";

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/* create a file containing 10 bytes */ : @' b4 R4 ]: A' Z. I# Fhandle = open("NEW.FIL", O_CREAT); if (handle > -1) ! ^) k& `6 O( z; U{ ) W& Y9 B& J: `, R$ D3 wwrite(handle, buf, strlen(buf));

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/* close the file */ close(handle); } 4 s$ p5 y+ I$ E. k" Gelse { : N r8 T, ]. \. e7 Nprintf("Error opening file\n"); } 0 M" k8 |( O/ [0 p" k' _* Hreturn 0; } 8 T6 d# V7 T. I' U% q) r$ \ 4 w- |! i3 h$ G) S; ~

函数名: clock 功 能: 确定处理器时间 用 法: clock_t clock(void); 程序例:

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#include #include # t; Q# x$ [" E- y7 @& _1 R#include

int main(void) . U2 l$ S! k0 l! ?; D Q" Z9 _# M{ 5 I6 Z8 Q% N( s; k5 lclock_t start, end; # S! n6 K4 g& t6 O0 a1 cstart = clock();

delay(2000);

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

return 0; + I, O2 |: e6 m} * W2 U0 f, N, ~2 E7 ?( ]1 q 0 v7 ]3 C' z8 a K8 q _& `

函数名: closegraph ( z5 r" | R! a% }功 能: 关闭图形系统 用 法: void far closegraph(void); $ s$ Z4 i ~8 X6 D& ~' a程序例:

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#include #include $ t1 L9 p1 |- [' i& t#include #include

int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; * L% u) T6 t6 ^+ ^& v5 jint x, y;

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

/* read result of initialization */ 1 Q' w& B) n1 @errorcode = graphresult();

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if (errorcode != grOk) /* an error + g+ P/ Y" i! \1 poccurred */ { d$ d7 E% T( L( D* D4 |$ oprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ ; `% I: m3 \' }; z8 m! B* P}

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x = getmaxx() / 2; . z3 ~! { E7 M% |9 |; Q4 Uy = getmaxy() / 2;

/* output a message */ & [7 j% f! |( [- s Dsettextjustify(CENTER_TEXT, CENTER_TEXT); / Y. g6 `5 I jouttextxy(x, y, "Press a key to close the graphics system:");

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

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

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); return 0; }

函数名: clreol : P2 A! f& ?/ Y功 能: 在文本窗口中清除字符到行末 - f2 s$ A' G; s" y! }用 法: void clreol(void); ( I# Q" X5 f2 K4 v) o: t# G8 `程序例:

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#include

int main(void)

{ clrscr(); 0 P6 r+ W6 n4 I# N( O K& F" icprintf("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 . . ."); 2 b) R, i/ x# ?5 {; ~# \gotoxy(14, 4); getch();

clreol(); 3 ?4 t6 r$ V) vgetch();

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return 0; . T# i: C. M. e} 1 w! X+ M6 R5 t* N

函数名: clrscr - t5 W- v* b$ O( n1 H功 能: 清除文本模式窗口 " v, c/ {. g, N S0 J0 I用 法: void clrscr(void); 程序例:

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#include

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int main(void) { t* w5 T7 q/ Gint i;

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clrscr(); for (i = 0; i < 20; i++) cprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); ( m% L9 g* ~8 Q5 M4 `( m# V9 ~* Ngetch();

clrscr(); c& p. B2 V2 t3 Y4 B' t4 Bcprintf("The screen has been cleared!"); 4 c6 D! `4 \ R- V1 ggetch();

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return 0; } $ ?: _$ C: r8 w, L

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函数名: coreleft $ G) h' e4 ^' [0 j8 R功 能: 返回未使用内存的大小 2 u" V% F [% o& O" q7 }用 法: unsigned coreleft(void); 程序例:

#include ) [/ L$ `7 A$ J- n" } @$ }#include

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int main(void) { printf("The difference between the highest allocated block and\n"); * o3 {8 E% I! i0 w& s3 ^printf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

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函数名: cos 功 能: 余弦函数 : R2 U( L+ { r# W6 M% l8 U4 Z用 法: double cos(double x); + F$ }+ L7 U6 Z% |3 O; H$ q- j程序例:

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#include 1 Q& P! C) S2 t) k W#include

int main(void) { double result; . E8 J0 q" T7 [0 O9 z0 ^! S' N2 ^double x = 0.5;

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result = cos(x); printf("The cosine of %lf is %lf\n", x, result); & g! P( @9 N f% h2 ?7 F- [return 0; 3 l, ~# u! a+ Y5 _3 J8 m: m} ) H/ F7 V2 G7 t/ F

函数名: cosh 功 能: 双曲余弦函数 用 法: dluble cosh(double x); ! F. j8 X7 g: z7 g! Y程序例:

#include #include

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

result = cosh(x); X2 o; b% k9 |printf("The hyperboic cosine of %lf is %lf\n", x, result); 0 z6 U2 y! |8 b; [! g3 l5 sreturn 0; } ; S; y# {9 i' E & l) ]9 u0 Y! I8 M( @

函数名: country : n8 i; S+ R; H6 J) Z: v% a! Q6 j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 x- V7 G/ H+ [# \9 D. K#include

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#define USA 0

int main(void) { {% z' v) u& H) jstruct COUNTRY country_info;

country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", : U" N$ M8 d y; x1 ccountry_info.co_curr); return 0; 7 X# c9 N* l4 W4 r} 5 K8 ]2 O8 H# k9 } J) a6 v

函数名: cprintf 功 能: 送格式化输出至屏幕 ) C# s' G+ H! r; F* q用 法: int cprintf(const char *format[, argument, ...]); 1 d1 r5 a8 {+ F, h& J3 R, E程序例:

#include

int main(void) { /* clear the screen */ 7 V% U+ P) D [/ `7 u1 bclrscr();

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

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

/* wait for a key */ - I0 e, [ f9 D5 r+ n4 N# D2 g. \5 l" y/ ?getch(); return 0; & O7 `9 I e+ V* |} ( X0 v5 b2 y, \

函数名: cputs x7 Q" M3 i1 f功 能: 写字符到屏幕 用 法: void cputs(const char *string); 程序例:

#include

int main(void) { ' e8 B) j. ?9 |. _- w/* clear the screen */ clrscr();

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/* create a text window */ * [3 a8 f3 \$ ?9 W! t, T( T; y& wwindow(10, 10, 80, 25);

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

/* wait for a key */ , ~6 o, k& p/ l4 u7 z; r! hgetch(); ( B6 k) E: u5 b, Zreturn 0; * C7 c5 I/ g+ x}

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函数名: _creat creat 9 H7 v: z: a# Z# q0 ]功 能: 创建一个新文件或重写一个已存在的文件 " u: V# S8 [) \! W8 [% ^6 e用 法: int creat (const char *filename, int permiss); & o6 l& y/ |/ F+ {- n程序例:

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#include #include ; R/ J! `- H* Y" H" Q% V7 O#include ' t5 I! N$ X& p% m#include

int main(void) { j5 Y9 c' {( h! iint handle; char buf[11] = "0123456789";

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/* 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 */ write(handle, buf, strlen(buf));

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/* close the file */ close(handle); # c% i5 F5 n! G7 Breturn 0; } ) b: w; T4 k0 n% V0 D

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函数名: creatnew $ b8 l% k3 t7 b4 F G+ `4 n) u功 能: 创建一个新文件 1 q7 N3 C- E& Q5 D b0 v用 法: int creatnew(const char *filename, int attrib); 5 |" }$ @. |; Z$ Q' L程序例:

#include #include 6 P( c6 }, `( i: }/ z#include , f4 ?/ k7 d* y# B0 u#include - f% |* W- `8 a0 D#include

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

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

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if (handle == -1) ; x+ }, c. d/ \5 n$ O6 mprintf("DUMMY.FIL already exists.\n"); ( c2 }8 l& i6 ^5 i- A: M, ~" belse $ M7 y7 |0 X% @$ @0 u* n{ & @" _! I; p6 o* ^! C: Kprintf("DUMMY.FIL successfully created.\n"); 2 h5 {$ e% s' i/ O E1 K# Bwrite(handle, buf, strlen(buf)); close(handle); 1 Y5 x( l, o3 K# i# y# J8 r} return 0; & i7 c0 u' Z9 ]& P$ |8 y} 3 U! M5 R+ h, ~) ~: U

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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 用 法: int creattemp(const char *filename, int attrib); * O7 ^" {, o! \8 u h* k+ F& v0 H. F程序例:

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#include $ P6 {2 |) V; u+ ?2 T#include 9 S) n! Z' v. i, f2 z- X6 B o" I0 H3 H#include

int main(void) { int handle; , I: d9 y" D) nchar 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); & z1 ?5 ^; Z) R2 n! C Wreturn 0; 6 U* y8 b3 Y5 E( o1 ~1 ?% a} # ?# S$ M D6 G) K2 i, C" ?& N* V 2 ]% J0 Z0 v7 j; ~# h5 ]3 Z 5 r- G+ u2 K- W: i0 V, M

函数名: cscanf 1 {) W3 T4 W9 a! H功 能: 从控制台执行格式化输入 / d2 j, g; c+ t$ V) E用 法: int cscanf(char *format[,argument, ...]); - n, @5 d; T. [8 |1 ^# E程序例:

#include

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int main(void) 9 |. v+ ~& P' r) N7 D, _6 Z{ # u ^2 U0 _9 {3 |2 N* Ichar string[80];

/* clear the screen */ 8 h% Z& w4 y; T! w/ B. A, ]. @clrscr();

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

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/* read the input */ }2 F1 l, Z/ l3 ^# B# Xcscanf("%s", string);

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/* display what was read */ 5 ^" e% q8 [3 Q% o6 f2 H' Ucprintf("\r\nThe string entered is: %s", string); return 0; } 6 F# s" M+ f/ B6 D+ E % m% I( Y9 P8 l

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); 程序例:

#include #include

int main(void) { time_t t;

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time(&t); ) L; P' Z. P% B1 A6 k( W& J1 hprintf("Today's date and time: %s\n", ctime(&t)); * e) h) x& b# Dreturn 0; }

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函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); , k" x; j3 I8 C- b程序例:

#include #include

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#define ABORT 0

int c_break(void) { - o+ c* v, T6 Z; |3 {9 N# o2 Wprintf("Control-Break pressed. Program aborting ...\n"); return (ABORT); % v' ]# u" C1 d# r% l& l}

int main(void) . p" J" h: W+ ?{ 3 i8 B" l# ?2 f1 H0 M4 Actrlbrk(c_break); for(;;) { ; j( L$ J+ [& @printf("Looping... Press to quit:\n"); 2 _' J# @+ s) n3 E+ D} / x' v5 w, i# e- x, qreturn 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