函数大全(c开头)

韩冰

函数大全(c开头)

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函数名: cabs 3 `5 X8 Z+ N3 h功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); ) u( i/ `) b$ D1 z$ ]程序例:

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#include #include

int main(void) 4 i! f$ H, `1 M* A. o# n( k{ / O& M+ c4 r, o! d- A- L) i0 \struct complex z; double val;

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z.x = 2.0; z.y = 1.0; val = cabs(z);

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printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; }

函数名: calloc , t/ j u3 n( U( r$ m2 Q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 1 Y3 N8 l. ? k- h3 k#include

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

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/* allocate memory for string */ ! T& `1 }- [8 z& j6 k5 kstr = calloc(10, sizeof(char));

/* copy "Hello" into string */ strcpy(str, "Hello");

/* display string */ : l- h. m; Q+ Dprintf("String is %s\n", str);

/* free memory */ 0 ]# s; r! u k" Ffree(str);

return 0; } 7 t, k( m% y9 s6 B6 G ; y/ P) D& W2 y" n8 Y3 w " e( C, f% M( A0 A

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函数名: ceil 0 `6 ^- [2 F( H0 s& [功 能: 向上舍入 ; j$ a7 q5 D; e; l/ e( z! \: n用 法: double ceil(double x); ; H1 N6 m$ ]" \程序例:

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#include #include

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int main(void) { ( W% R! B1 Y8 q7 h- c5 Jdouble number = 123.54; 2 R' N9 A9 I; h1 W3 t% gdouble down, up;

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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); ( A5 G5 E% H4 ?" Fprintf("number rounded up %5.2lf\n", up);

return 0; }

函数名: cgets ) ? ]6 k# c/ T: c% Z功 能: 从控制台读字符串 用 法: char *cgets(char *str); ) ~' ?4 ^( w: n* h% q2 y5 x程序例:

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#include #include

int main(void) 4 A( K6 }0 Y7 E+ }8 {; s- D{ char buffer[83]; char *p;

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/* 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);

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/* Leave room for 5 characters plus the NULL terminator */ 2 {- s) A# _, y9 a) ]# rbuffer[0] = 6;

printf("Input some chars:"); # }: C& z- n, M1 {, G/ jp = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 3 ?7 p6 G/ J" \printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); return 0; } # F; a/ `5 R5 Q8 h5 \. z

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函数名: chdir 7 q8 B4 o- A0 k: p& F- d功 能: 改变工作目录 ' r* t0 ?* Q" p; \8 ^用 法: int chdir(const char *path); 程序例:

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#include : e h5 Y9 \, y, p#include 8 e! J! N9 v" A4 z# k. y#include

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char old_dir[MAXDIR]; # C: z9 {/ B6 |6 {$ D9 g5 Fchar new_dir[MAXDIR];

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int main(void) , A! R* _ W/ L( s% K3 i& B/ W- Z{ if (getcurdir(0, old_dir)) { J+ t, `7 [( k- Tperror("getcurdir()"); 8 E* Y) y; D: x ?: kexit(1); } printf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) + m9 J2 v4 _/ A8 p4 F: s6 I{ $ |: q3 B! |1 s, `$ x, [perror("chdir()"); 3 c$ B& Y. ?$ o# c8 Dexit(1); }

if (getcurdir(0, new_dir)) # `) g/ O1 L/ n2 u3 w% _8 v{ perror("getcurdir()"); exit(1); $ N* W; s* g4 b; |} printf("Current directory is now: \\%s\n", new_dir);

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); ( V3 i' ]* M" r! A9 J" d& Zif (chdir(old_dir)) , W! B8 U q, C1 N{ perror("chdir()"); exit(1); : o- _) m. a1 C I" P5 x% w: j6 r}

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return 0; 5 @% C4 _2 }) `+ w% a} " g. U3 N) b9 r( K& [

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函数名: _chmod, chmod 功 能: 改变文件的访问方式 a% k1 N8 c- _用 法: int chmod(const char *filename, int permiss); 程序例:

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#include 8 f& ^6 L: x! y3 K#include 4 c# H) |4 X; N' G4 f( W3 Z#include

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void make_read_only(char *filename);

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int main(void) { make_read_only("NOTEXIST.FIL"); 5 Y# O/ \. M; k8 J- J3 x# ?make_read_only("MYFILE.FIL"); return 0; & Z- A. V5 G1 p) T' [" ?4 j}

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void make_read_only(char *filename) . ]. [8 Z' S: H3 k6 A0 v6 Z{ $ N( T0 W' ]* f/ n* y, Pint stat;

stat = chmod(filename, S_IREAD); if (stat) printf("Couldn't make %s read-only\n", filename); 5 S' \! b1 ]& selse printf("Made %s read-only\n", filename); } 0 c$ C9 Z) f0 U" P1 h9 n8 |* | Y0 l

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函数名: chsize 2 m. e1 U" _% u7 G功 能: 改变文件大小 . M8 `1 V8 @3 V+ C# H8 }; Q, i用 法: int chsize(int handle, long size); 9 X1 s4 m2 X' w程序例:

#include " R% }0 L' }7 K7 o2 J8 v#include + @+ u. T9 X9 E0 l1 G4 F: w* A#include

int main(void) " p$ l* {( E4 U S( a{ $ t8 y9 k4 e, _4 n& }int handle; char buf[11] = "0123456789";

/* create text file containing 10 bytes */ handle = open("DUMMY.FIL", O_CREAT); + K! s# t* _$ l! N. _1 Lwrite(handle, buf, strlen(buf));

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

/* close the file */ 4 i, @2 u9 W% Qclose(handle); 6 {7 O: ?+ I. v: T" R; Dreturn 0; } 1 z) G5 v* I* j3 j4 \+ n, ^# G

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函数名: circle ' X3 I% _: X5 U& \) H) F! S$ N" X4 B功 能: 在给定半径以(x, y)为圆心画圆 用 法: void far circle(int x, int y, int radius); 程序例:

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#include #include #include * H1 J$ u. _: @: r- k#include

int main(void) { /* request auto detection */ 8 O1 q# a0 t% d2 k$ x0 W8 z3 Mint gdriver = DETECT, gmode, errorcode; int midx, midy; % r9 i8 w& ^9 a4 u7 b3 |* t, E6 mint radius = 100;

/* initialize graphics and local variables */ 2 c) q3 f. A) J; K" Vinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ' K- S7 K; } [$ d5 @) eerrorcode = graphresult(); ; F4 L( @5 o) }2 e& iif (errorcode != grOk) /* an error occurred */ { $ ]8 j6 L0 ?* z4 f$ ]printf("Graphics error: %s\n", grapherrormsg(errorcode)); # w3 n$ v7 f" [8 I+ I, V* Z) @% Gprintf("Press any key to halt:"); getch(); " x- t# r, \; @; W# \exit(1); /* terminate with an error code */ 3 q3 l3 \5 u, n8 x* ?$ x. p/ X9 S( j5 q}

midx = getmaxx() / 2; midy = getmaxy() / 2; ; y0 u& F! f: t" ~: Csetcolor(getmaxcolor());

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/* draw the circle */ % U. o, X: _& Qcircle(midx, midy, radius);

/* clean up */ getch(); # K ?% W/ p% O8 j+ Fclosegraph(); - V3 K. U3 W! {/ ` Dreturn 0; } + S8 A% ? t) _& ?" R4 y " S6 ^6 k9 z4 w) \

函数名: cleardevice ' U3 m& S4 ?1 x X1 p8 a功 能: 清除图形屏幕 用 法: void far cleardevice(void); 程序例:

#include #include q6 N% v' p \& m( A1 ?$ o#include , ~; K. N. N8 p#include

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int main(void) # H7 B" l$ e3 ?# `: J{ /* request auto detection */ $ q) V# ]: b6 A6 e- E) g/ Wint gdriver = DETECT, gmode, errorcode; 9 Y/ H9 f& G$ g( g: k: aint midx, midy;

/* initialize graphics and local variables */ # G `0 f, ^0 ~1 v4 Qinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ errorcode = graphresult(); 4 ~2 g5 w) `: J# d5 b& u& Oif (errorcode != grOk) /* an error occurred */ 7 K" x2 m3 i7 w, c" B+ I9 H: R: Z, i{ 9 ~3 O o. q" J2 w5 I+ h. Z+ M1 gprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 7 Q1 E" C8 G' q6 Zprintf("Press any key to halt:"); getch(); # w& Y' P: U& s, h5 V; Sexit(1); /* terminate with an error code */ }

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midx = getmaxx() / 2; - d! o+ b3 G8 |midy = getmaxy() / 2; 9 l# Q1 V* z/ s+ x4 F, D$ i/ dsetcolor(getmaxcolor());

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

/* output a message to the screen */ 2 y l. T- R% l' m# k2 routtextxy(midx, midy, "press any key to clear the screen:");

/* wait for a key */ . O- W3 B% Y/ w' p1 ^9 W7 C9 kgetch();

/* clear the screen */ cleardevice();

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

/* clean up */ ; R u+ ^# b1 Ggetch(); % Z5 _, T( V8 q3 Rclosegraph(); return 0; 4 |5 o4 ?8 U# j2 F Y} 4 U0 ^8 S( r' |. e8 ^: m; u) Q5 h2 Z. _ " x& _& g0 \# `1 w* l! o2 y

函数名: clearerr , H+ c }- S* t% d& A功 能: 复位错误标志 % l4 Z6 ?4 W& W8 ?用 法:void clearerr(FILE *stream); ( j+ i1 K a0 Y" r `6 `& C0 y程序例:

#include

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int main(void) { FILE *fp; char ch;

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

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/* force an error condition by attempting to read */ ; V! m( s8 S5 tch = fgetc(fp); # L) a* L+ u' I2 qprintf("%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); / o4 A% \ G- f3 Y/ O( \}

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fclose(fp); - [$ }0 ?0 V, `8 n, R5 Oreturn 0; } ) }1 q7 s5 k. q% o' I' E+ m . D$ c# ~9 n; ^. X

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函数名: clearviewport 功 能: 清除图形视区 用 法: void far clearviewport(void); 程序例:

#include ( m; x$ l3 D9 J/ p) T+ g#include , _, g1 ^+ n5 S t0 p8 R: n#include #include

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

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int main(void) { 5 \& p! \* D3 b9 H/* 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(); 3 R# a: G! J% c2 d8 cif (errorcode != grOk) /* an error occurred */ 6 `( T, x: `: y1 o2 u{ + j( b: b+ O' Q9 N0 E+ kprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 7 {5 n% F2 v7 p0 r+ V/ cprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ % u0 G! G8 s1 v}

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

/* message in default full-screen viewport */ . P0 |2 c& t! C souttextxy(0, 0, "* <-- (0, 0) in default viewport");

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

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/* display some messages */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); " N, m% |, V% o1 n0 z2 f/ Qouttextxy(0, 2*ht, "Press any key to clear viewport:");

/* wait for a key */ 1 h, u" }# h2 x+ P( i" g; m' j# Rgetch();

/* clear the viewport */ clearviewport();

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

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/* clean up */ getch(); / g5 K* G, h+ \ |7 P( R& Gclosegraph(); # u% `0 Z4 i) R) \% Rreturn 0; } ( i' L8 } Y$ j% g# s5 |

函数名: _close, close 功 能: 关闭文件句柄 用 法: int close(int handle); 程序例:

#include . @; G+ n2 T# E* z8 B2 W- |+ M4 z j#include #include 5 v" `0 T; A. \: w! ^. ~#include

main() % L% e( y) `; K8 m3 O{ 0 `# Y9 y- s) q2 ^2 z6 dint handle; char buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); % G6 J( U! Z* Rif (handle > -1) / c: Q5 l* V( w. r{ write(handle, buf, strlen(buf));

/* close the file */ close(handle); } 0 w/ N# V* f" oelse { $ L2 H6 y( q0 p' Bprintf("Error opening file\n"); 3 x9 H2 L9 ~) w} return 0; % U: \3 v3 b4 ~+ [} ) R9 U) ]) L" y ; p/ g, @1 ^+ g8 f' M. W x# q1 u, f6 c$ Z+ ~5 B

函数名: clock 功 能: 确定处理器时间 0 r5 \' X! L# G, P1 h; `用 法: clock_t clock(void); 程序例:

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#include ; a0 y( d2 }" u6 I( g#include , _7 R" n! C8 b4 ?+ t#include

int main(void) { clock_t start, end; 0 {; r% o8 i5 B* j' o# t6 ~, Astart = clock();

delay(2000);

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end = clock(); $ o) G7 O! a3 H& l- Lprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; } ) |9 P1 Q) {9 w8 l( B4 p $ D5 d1 g# C% P- U* K

函数名: closegraph - l' O8 k) `6 f功 能: 关闭图形系统 . N5 w. G, ]4 w9 U% j" @% Z用 法: void far closegraph(void); 程序例:

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#include 1 ?# D+ O6 L1 Y$ J1 e! t# Y#include #include 7 T* p2 s$ O a: h#include

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int main(void) { 4 d& O! L4 A* O) r, d& z5 `( u/* 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 ! t4 ^3 K( z. G& foccurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); ! c9 ?: S" K% M+ zexit(1); /* terminate with an error code */ }

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

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(x, y, "Press a key to close the graphics system:");

/* wait for a key */ + `! z( W+ S5 i4 y; L/ x5 Hgetch();

/* closes down the graphics system */ 9 @5 b7 R% F( W4 iclosegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); + R' }; S; i" Bgetch(); return 0; } 1 [0 r5 E' L) G. P" G' n0 N/ | ' r# Y" N$ _2 `0 d! {3 i s1 j& b/ v" P: R

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函数名: clreol - r* j! }; {% }0 R功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); & x) ~* k6 K( m6 b Y" M程序例:

#include

int main(void)

{ clrscr(); " U- U" d/ A- l+ L' @cprintf("The function CLREOL clears all characters from the\r\n"); 5 z8 ^ F: J& |! U: }# Ycprintf("cursor position to the end of the line within the\r\n"); 4 z7 B, q; ^7 h8 c4 r; G' r" Mcprintf("current text window, without moving the cursor.\r\n"); + d+ ^! }" @7 dcprintf("Press any key to continue . . ."); gotoxy(14, 4); getch();

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clreol(); ! \: b/ h: h5 c4 Igetch();

return 0; / v# z6 U& `6 @- R} 3 b+ Q/ d c. }, \6 n& F 7 v0 ]# C, V" q8 [$ f* m7 j: o% T

函数名: clrscr 功 能: 清除文本模式窗口 + e& Q+ h8 l& M2 q8 J k用 法: void clrscr(void); 程序例:

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#include

int main(void) / e! b3 \* n& a7 [7 Y4 P{ int i;

clrscr(); for (i = 0; i < 20; i++) 6 p! G& N& h- L! }2 s3 ucprintf("%d\r\n", i); cprintf("\r\nPress any key to clear screen"); getch();

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clrscr(); 5 A! Q. A, |) ^cprintf("The screen has been cleared!"); 8 d0 c- e) G7 C5 c0 ?# q+ ]getch();

return 0; } # Y" t4 H5 ~7 I8 R b u( {7 l7 a 3 E6 P, h0 G1 `

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函数名: coreleft * C9 q* W7 E3 ?$ i! z$ b. c3 k/ u功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); * G1 l( S) T. r5 `) }) c) J2 L程序例:

#include #include

int main(void) { , G- p" b6 {# H6 ?) r. t$ }) yprintf("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; / G! l9 o( J7 s# u% [ f9 p4 `}

函数名: cos 功 能: 余弦函数 $ S% l3 ?2 A4 h0 t0 {) J" }用 法: double cos(double x); - F) _. h( y; E3 l: Y& a程序例:

#include #include

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int main(void) ( j' h) m+ [# O7 `{ F& @: Z# P4 L) V% O( ~2 L& Edouble result; double x = 0.5;

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result = cos(x); Q/ `6 @0 P# e7 U+ y" Mprintf("The cosine of %lf is %lf\n", x, result); return 0; & N6 ?4 }( |5 Q4 O} ) t5 L7 O! C. [

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函数名: cosh * N# p. D! v+ ~) y+ `功 能: 双曲余弦函数 用 法: dluble cosh(double x); 7 Q) z8 z3 \7 X* E* [/ `" H( |程序例:

#include ! j X% u2 v4 H. P/ _! V A#include

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int main(void) { double result; : `; C- c8 P7 n5 J) [+ }7 J2 D% y0 Cdouble x = 0.5;

result = cosh(x); 4 t' I3 S* r d$ i0 V6 yprintf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; } * M+ M5 i+ h. u! G - h# J# `* [1 B3 N5 C Q

函数名: country 功 能: 返回与国家有关的信息 ) a' x/ ]9 j; |0 g+ G- ?6 S用 法: struct COUNTRY *country(int countrycode, struct country *country); + U4 G I" P! y$ W程序例:

#include 7 c* h" @# M l/ J% L8 p+ ^#include

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#define USA 0

int main(void) { + A% |7 Z% O& T$ Z$ zstruct COUNTRY country_info;

country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", & U$ Z$ \5 x& v2 X9 [ N5 ^country_info.co_curr); % m4 [1 ^9 V; F( Oreturn 0; } - T3 [- V% o7 K3 C5 H" C

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函数名: cprintf 功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); ) \" B+ i: G, [; T7 m2 J程序例:

#include

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

/* create a text window */ . ^6 i; B% B3 E( ~window(10, 10, 80, 25);

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

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/* wait for a key */ - \9 `, x( s- pgetch(); return 0; } ) W4 s( @9 {7 E

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

#include

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int main(void) { 0 K7 n1 y- l! }8 ~/* clear the screen */ 5 p- l9 |; ?) {" H% x ^& h% H3 Tclrscr();

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/* 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 */ : a- C: R( v3 J* lgetch(); return 0; / y4 G' ^* k' @9 q7 m} " r3 e# e$ N( M. k, M! `5 x$ [ 7 b: w2 V( T' |6 r

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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); 程序例:

#include 0 @' T7 x$ ]( i9 i#include # i9 C6 j! \; E) ?. }. d; `0 n. N#include #include

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int main(void) 7 d3 R, a5 d1 G0 t{ z3 q6 v! o3 R B* |: Z0 \int handle; char buf[11] = "0123456789";

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

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

/* write 10 bytes to the file */ / d8 Q0 r, X1 k# ?; K3 Nwrite(handle, buf, strlen(buf));

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/* close the file */ close(handle); , l; M) L" i$ J2 b' D( Hreturn 0; S/ e0 e. \) F, G* a2 j}

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函数名: creatnew 功 能: 创建一个新文件 6 g5 b, _' @# P7 @6 H用 法: int creatnew(const char *filename, int attrib); 程序例:

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#include #include #include #include ; S0 F0 q+ w. s5 K/ @/ R#include

int main(void) " ]2 b- a c* n$ N, t" G* [{ ' X; {8 T, t4 p9 C4 \$ A% o. z1 Xint handle; char buf[11] = "0123456789";

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

if (handle == -1) , R* R a8 P$ I, Q1 E* E& Nprintf("DUMMY.FIL already exists.\n"); : O2 P: ^% S Q, O) ]1 F, {& F# celse { $ h3 m( R' r' Yprintf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); close(handle); } 3 Q3 t3 E7 D+ h9 I. e1 f4 V3 o8 v& U; jreturn 0; - C1 W$ P' ^5 q' H} $ j6 c1 c4 [0 ~. j

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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); 程序例:

#include 5 [$ K! v0 @6 L q8 _+ G; h! r#include & L( C" W8 e6 @8 }* Z: e#include

int main(void) j% }7 w' ~2 K2 Z: j{ int handle; 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); ) j7 [! k! }% N4 P* L/ ]return 0; } ( Z4 \6 H& l: j1 ^" I

函数名: cscanf 功 能: 从控制台执行格式化输入 % }- a: `, d0 w用 法: int cscanf(char *format[,argument, ...]); % [5 c( H0 J; b3 H8 A程序例:

#include

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int main(void) 3 a/ `2 N9 }8 c- H{ char string[80];

/* clear the screen */ ) b9 K& d3 @) zclrscr();

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

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/* read the input */ & Z' D& f1 D; S. ]0 @6 Icscanf("%s", string);

/* display what was read */ : ^& M( P1 ?: X+ W: s. [/ m( w# hcprintf("\r\nThe string entered is: %s", string); : o I1 Q+ d$ N& n1 oreturn 0; " S; n0 X4 r! r% P% }4 f4 F} / _: N/ Q4 _' K$ A& ?( Q7 }4 s5 D / T0 W8 v. B" a" b

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函数名: ctime 功 能: 把日期和时间转换为字符串 W$ u+ H. R/ ~! ~" c用 法: char *ctime(const time_t *time); $ \9 q- ?4 L7 ^! x& c3 ?- w程序例:

#include % K. }/ N) Z. B9 w#include

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int main(void) : ~& q5 \8 C C{ time_t t;

time(&t); 9 Y2 O0 c# r7 f1 q( x6 x# ^printf("Today's date and time: %s\n", ctime(&t)); ) g7 o9 m5 o' B% jreturn 0; 8 i+ m6 e, q- p; J9 [! r" m% \} # |, W$ S- d( n' ?

函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 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"); return (ABORT); ! h2 v/ I! E6 ^, G. \}

int main(void) { ; V; g' g, a# k+ b6 ^9 Ectrlbrk(c_break); for(;;) { & x- _- K) P# H( N q7 C3 U$ L! R: mprintf("Looping... Press to quit:\n"); 7 S# w; ] i/ c3 P) B} return 0; }

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[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