函数大全(c开头)

韩冰

函数大全(c开头) & b5 n# @! {, ]3 x( I2 ]# D {

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函数名: cabs 4 H( J/ L! A* H, O( Z功 能: 计算复数的绝对值 5 p3 V; {8 ^3 P Z5 R& z4 d用 法: double cabs(struct complex z); 程序例:

#include #include

int main(void) { struct complex z; - L& A7 W" n+ g5 K: Sdouble val;

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z.x = 2.0; ' N7 o( S1 [, a- H' dz.y = 1.0; ( ?* N. _8 D& z. bval = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); ; l I! [8 B9 w6 I h& Oreturn 0; }

函数名: calloc * ]) @2 b% p0 E8 c/ B0 x% r1 |功 能: 分配主存储器 ; n i2 `& c; }: ?* l9 w/ Z- X用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include 4 M4 R( U! ]0 A#include

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

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/* allocate memory for string */ ; ?4 S# G- M& ^0 D6 u" {str = calloc(10, sizeof(char));

/* copy "Hello" into string */ 5 Y. Y8 w$ F2 H0 rstrcpy(str, "Hello");

/* display string */ / S8 W. N- X: G: mprintf("String is %s\n", str);

/* free memory */ " |' S/ v7 h, B5 _" R; `3 V5 v* \free(str);

return 0; } ! T+ T, }/ z, t+ e$ w5 i( F

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函数名: ceil 功 能: 向上舍入 E" z! x$ U0 K! T6 i9 y4 G* c用 法: double ceil(double x); 程序例:

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#include #include

int main(void) { double number = 123.54; & ?* @. R8 @! L" I# F# x1 y1 y) k$ |double down, up;

down = floor(number); 3 W4 M/ N/ i/ W6 qup = ceil(number);

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printf("original number %5.2lf\n", number); printf("number rounded down %5.2lf\n", down); / P0 y7 w3 k! G t9 `printf("number rounded up %5.2lf\n", up);

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return 0; : Q* @5 v5 T7 R3 E! k1 C/ m} , i2 {! D$ H3 l6 B+ U8 O7 K6 H " a+ Y5 K! i# Y6 f$ m7 e

函数名: cgets 功 能: 从控制台读字符串 用 法: char *cgets(char *str); , |* E% E6 q9 l5 B% l P程序例:

#include 5 o0 a1 h7 w( ^* g#include

int main(void) ' g9 B/ T; c! s. g{ 0 B' r1 A7 T/ G8 \/ K9 Rchar buffer[83]; char *p;

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/* There's space for 80 characters plus the NULL terminator */ % j. O: j+ J* _1 ^) e! Hbuffer[0] = 81;

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printf("Input some chars:"); 1 \. r8 X6 S; P' U: D2 np = 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 */ + ~" W. D3 G: q1 |3 _buffer[0] = 6;

printf("Input some chars:"); / ? w- n. h, r4 I( B* Vp = 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); : r6 y, B- O& l5 x$ t2 |5 ~return 0; / O- J# J. m6 _, a/ V% c} ) R: G/ x2 S7 V0 }" K- B

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函数名: chdir 2 f0 B. j( i A) M7 H功 能: 改变工作目录 用 法: int chdir(const char *path); ( Y4 R0 I0 L N: T; z程序例:

#include #include #include

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

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int main(void) { j# r0 e% k; ^, k9 F9 I$ Sif (getcurdir(0, old_dir)) { perror("getcurdir()"); exit(1); & M/ n" i ^1 ^& Z3 z} 5 _' P" S6 U; A- j, ^printf("Current directory is: \\%s\n", old_dir);

if (chdir("\\")) % H1 q' n! c. l/ x% ~0 X7 l{ perror("chdir()"); * c" K2 O) }) l5 u3 p, D) p8 jexit(1); }

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

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printf("\nChanging back to orignal directory: \\%s\n", old_dir); % M6 E5 V* d5 c% ^ ~if (chdir(old_dir)) { 0 m# `3 d) Q/ X/ w8 J9 \1 ?2 t8 \" wperror("chdir()"); ' Y1 q+ L6 }4 t& I" X1 I- W, Gexit(1); }

return 0; : [! E" \( \( `/ \4 w3 h4 ?}

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函数名: _chmod, chmod ; j9 |* J( ~$ T/ l6 \功 能: 改变文件的访问方式 & Q% T$ ~2 k9 R& C5 f用 法: int chmod(const char *filename, int permiss); 程序例:

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#include #include #include

void make_read_only(char *filename);

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int main(void) t$ m/ _9 T( H9 S. b" j) a8 W{ make_read_only("NOTEXIST.FIL"); ( x% Y) N" Z) d- Rmake_read_only("MYFILE.FIL"); return 0; }

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void make_read_only(char *filename) { int stat;

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stat = chmod(filename, S_IREAD); ( A; g* }8 p$ p8 N1 wif (stat) . r- V; q J6 R. p( l- nprintf("Couldn't make %s read-only\n", filename); ' p: I5 f! f% p- D5 E* f/ Helse printf("Made %s read-only\n", filename); } - \8 V1 }. E. Z, T: H& v4 y" A : l. S$ A$ ^$ @" D* D# E

函数名: chsize / w* K) e3 x: A- S功 能: 改变文件大小 ; N/ s! c0 F2 X5 b, q6 Y用 法: int chsize(int handle, long size); 程序例:

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#include #include . G5 V- o( T$ y5 h, t) L#include

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int main(void) * K1 f4 Z' I1 t2 A& G9 ]1 L{ 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 */ 7 j$ a3 K( Q& k, o I- t7 ~close(handle); 0 O3 e1 G$ J9 n2 W" G, E6 dreturn 0; * ]' I& C# v- z' S) @6 n3 V9 s} # ?; g& i% G* S& k

函数名: circle V8 H' N& C; q. n3 @功 能: 在给定半径以(x, y)为圆心画圆 7 [) }- ?8 G8 _3 T0 i用 法: void far circle(int x, int y, int radius); 程序例:

#include - b+ A" E& k# c: ^, t#include #include #include

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int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; + z2 o/ C; Y* D+ F1 D0 {7 r$ Uint midx, midy; int radius = 100;

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/* initialize graphics and local variables */ ) a% w+ q2 ]6 Z& i0 M4 M' pinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ # S$ b6 l) r0 t8 D8 k# ^{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); 9 K" ]8 S/ R% E& g. c8 ?) Tgetch(); exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; & V! N& I8 a1 \! Wmidy = getmaxy() / 2; setcolor(getmaxcolor());

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/* draw the circle */ 1 ^* N/ z4 m8 g4 [2 D rcircle(midx, midy, radius);

/* clean up */ ; V) |9 A/ h7 v6 @. p* Kgetch(); closegraph(); 1 G3 R" d) U+ @6 m/ [( Oreturn 0; } $ i9 K) s e" ?6 l4 z7 J4 v 4 V3 s# A% m# q! k - T3 X1 C. t; p4 s( T

函数名: cleardevice 功 能: 清除图形屏幕 用 法: void far cleardevice(void); 4 y' G% @4 h4 F! Y" t5 p程序例:

#include 2 {# J# M; {; ]8 v#include #include % j9 h: J# O, s; n# Y#include

int main(void) { 3 [. ~, r5 L) _! x" V/* request auto detection */ int gdriver = DETECT, gmode, errorcode; 7 c( j6 ^4 U& D# y. _4 Tint midx, midy;

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

/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); $ M t: ^1 H9 D. zprintf("Press any key to halt:"); 7 ]+ i8 e5 t" q0 Y9 N( `getch(); exit(1); /* terminate with an error code */ }

midx = getmaxx() / 2; & H" P# X: y" B `8 P# O1 K3 c; umidy = getmaxy() / 2; setcolor(getmaxcolor());

/* for centering screen messages */ % Z! K" |: b1 A6 z1 Z( xsettextjustify(CENTER_TEXT, CENTER_TEXT);

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/* output a message to the screen */ , v' V a( k" G6 i: B( [outtextxy(midx, midy, "press any key to clear the screen:");

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

/* clear the screen */ 5 {" L+ J: v- O" acleardevice();

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

/* clean up */ 9 p; r- u0 w) jgetch(); closegraph(); ! `7 [: ]! E4 `0 C" n9 a% c9 ereturn 0; }

函数名: clearerr 4 S" ] a; x. ~6 A- }功 能: 复位错误标志 0 B6 L, w6 S; l, u7 J# L$ R2 \用 法:void clearerr(FILE *stream); 程序例:

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#include

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

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/* open a file for writing */ 1 w- h0 m+ d8 T( ~fp = fopen("DUMMY.FIL", "w");

/* force an error condition by attempting to read */ 4 b. p3 [5 t/ Y5 Q+ L) Sch = fgetc(fp); - u$ e* v+ j2 N3 ^, qprintf("%c\n",ch);

if (ferror(fp)) { # W7 Y4 P0 w: T8 s! k% R/* display an error message */ $ i+ H* d* c7 }0 _4 l8 v; x$ ~printf("Error reading from DUMMY.FIL\n");

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/* reset the error and EOF indicators */ clearerr(fp); 3 H& U5 h0 Q5 U6 D# L% R}

fclose(fp); % Q" g# M( N+ p, m5 Y+ v4 Lreturn 0; ! w, T8 W8 @& L5 @: m `# Z! f) g} ! G/ |3 }- D V4 t3 B- }8 v " w( @& t1 ?3 h/ E+ [5 ?0 o4 P

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

#include # v9 C9 f6 D; k2 o# Y3 N#include + E& p- Z5 J3 }/ O. F! p0 L, V, l#include #include

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

int main(void) . Q' B+ D, q: v9 b) R{ 3 _+ X2 T$ X; {$ Q/* request auto detection */ # { j' H0 j+ Pint gdriver = DETECT, gmode, errorcode; & x K4 w1 K E1 b" f- V+ rint ht;

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/* initialize graphics and local variables */ + P7 ]( P/ t- Z6 g Rinitgraph(&gdriver, &gmode, "");

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/* read result of initialization */ 6 s. { I/ {2 ?) }/ L6 L/ D( Oerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); % `& ?% H& k' U5 q- eexit(1); /* terminate with an error code */ ) N2 v9 l: Z- F' f* g0 u- j}

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

/* message in default full-screen viewport */ 3 m2 A- ^5 g# souttextxy(0, 0, "* <-- (0, 0) in default viewport");

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

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/* display some messages */ % j: O2 e8 K P/ p: routtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); outtextxy(0, 2*ht, "Press any key to clear viewport:");

/* wait for a key */ . o; r$ H* Q/ c8 ngetch();

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/* clear the viewport */ 3 ~9 g* e9 y0 ~3 o# ^clearviewport();

/* output another message */ 5 S4 ` P5 u) O' _1 O, Z8 Iouttextxy(0, 0, "Press any key to quit:");

/* clean up */ getch(); closegraph(); $ q1 t: U5 C$ w( v' _return 0; 6 F+ x3 S( ?, ?& O( _' o}

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函数名: _close, close # M* J2 W4 H# L6 N# E$ U: `; T功 能: 关闭文件句柄 * K0 E% X3 d3 {$ y' `( g用 法: int close(int handle); 程序例:

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#include 8 O3 e, W+ L0 D# u4 B! X1 p#include #include #include

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

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); if (handle > -1) * {9 \ V% y/ l$ d# U{ ) C: f: G# C# s+ D+ i% Awrite(handle, buf, strlen(buf));

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/* close the file */ / D: x' z4 j: c7 x, x, fclose(handle); 6 l% E. O% @+ O, r: y/ [2 b} * q$ i' x( I/ R, J; o7 helse { ! ]: F' `4 F6 A* _5 k |! gprintf("Error opening file\n"); } * O4 `/ v! [) r; ?4 Z& P7 nreturn 0; } 4 {# r6 X/ V! B% |

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

#include #include 4 c# A4 W& u( i#include

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int main(void) { clock_t start, end; start = clock();

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delay(2000);

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end = clock(); C1 N" t$ y3 a9 Y3 Q9 dprintf("The time was: %f\n", (end - start) / CLK_TCK);

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return 0; ' K" s/ @5 S& ]- S& }} # b$ A4 M) R8 _: M3 x6 a2 m

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函数名: closegraph 功 能: 关闭图形系统 , f3 ^7 L- u+ n5 F4 ? G I用 法: void far closegraph(void); # s9 Z# i: i. p5 O程序例:

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#include #include #include #include

int main(void) { - w2 ], J, n; u# c) @( P/* request auto detection */ # L! `3 t$ L# Q- @; V5 `int gdriver = DETECT, gmode, errorcode; 9 c$ Q( O: {4 o4 ]- ~int x, y;

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/* initialize graphics mode */ * u: Y+ c3 |0 e- z* {( iinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ - f8 V+ Z: t4 u# d$ c9 yerrorcode = graphresult();

if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ & w* }+ F) p* `6 n8 A}

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

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); " e5 I& x% h8 I! v2 ?* uouttextxy(x, y, "Press a key to close the graphics system:");

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

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

printf("We're now back in text mode.\n"); printf("Press any key to halt:"); 4 v+ k1 \! q: u! jgetch(); return 0; } # A$ ~( r; Q/ Z2 g' e0 J 1 d/ I7 E4 [* V; ]& G ; @1 q( I' |! t

函数名: clreol 功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 1 {+ g( Y% H7 m8 b! D程序例:

#include

int main(void)

{ 4 ~# C) }8 ^+ Xclrscr(); cprintf("The function CLREOL clears all characters from the\r\n"); cprintf("cursor position to the end of the line within the\r\n"); 9 I* M& U, `1 N9 U& rcprintf("current text window, without moving the cursor.\r\n"); cprintf("Press any key to continue . . ."); gotoxy(14, 4); * [9 M2 f1 q& l* ~0 |# l& pgetch();

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clreol(); getch();

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return 0; ( D; p# Z: T6 J& V} ) N8 V0 r6 a1 ?0 P8 Q) @ 1 d+ j! ]3 Z, R$ w

函数名: clrscr 功 能: 清除文本模式窗口 # ?% J4 p# M& F9 s8 V* O用 法: void clrscr(void); 程序例:

#include

int main(void) " T5 o h) j ^! V; P$ M) t. |{ 2 [6 y' E6 W$ f+ Rint i;

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clrscr(); for (i = 0; i < 20; i++) cprintf("%d\r\n", i); " M2 N0 m; R" I, f/ v% I# Ccprintf("\r\nPress any key to clear screen"); getch();

clrscr(); cprintf("The screen has been cleared!"); getch();

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return 0; 6 \8 z1 y, Y- v6 h5 n1 N} 1 L: q3 @9 B- r

函数名: coreleft ; \ N* l3 p- [; F# k- s功 能: 返回未使用内存的大小 8 w* N0 X2 C2 g w用 法: unsigned coreleft(void); 程序例:

#include #include

int main(void) { 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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函数名: cos ( e7 u/ L$ e3 l6 k% T0 \6 K) I功 能: 余弦函数 用 法: double cos(double x); 2 M0 z$ Q7 W7 j L7 o程序例:

#include #include

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int main(void) ) a1 T3 B; M; `! ]( G' {{ double result; double x = 0.5;

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result = cos(x); " e/ C* i# V. j B" Nprintf("The cosine of %lf is %lf\n", x, result); 2 N6 |" y3 |4 R4 K+ Y, Jreturn 0; }

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函数名: cosh 功 能: 双曲余弦函数 " X; M% }: I# ?9 J( Q用 法: dluble cosh(double x); 5 V+ ~' v4 j8 k; ~/ W+ Q程序例:

#include ; F8 o' o# ? j8 {#include

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int main(void) * F6 G2 u. J/ E/ X/ v, ?( D{ double result; double x = 0.5;

result = cosh(x); ' C: G: n% i$ N4 V! v( Tprintf("The hyperboic cosine of %lf is %lf\n", x, result); 1 ]% m* W- h8 A& _& u, Lreturn 0; 4 D, l9 G) _! L8 _3 h- s$ b} 0 \" w' j+ C* j9 @' z

函数名: country 0 M+ {0 f. D; G7 L, ]功 能: 返回与国家有关的信息 & y" f ], j* U5 O. w8 N( { a用 法: struct COUNTRY *country(int countrycode, struct country *country); 程序例:

#include 5 w# z' N9 F& ~#include

#define USA 0

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int main(void) { struct COUNTRY country_info;

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country(USA, &country_info); 0 U' ` F- {4 s0 M1 H6 Rprintf("The currency symbol for the USA is: %s\n", 3 O0 q" L e* ] C. ycountry_info.co_curr); . ^: [3 f! F; R, D% m! D6 v2 Sreturn 0; } 9 J/ I: _4 `! q% e2 j. ^0 }

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函数名: cprintf 5 b/ x& ]! Y% J' N2 v4 }" D. s) o功 能: 送格式化输出至屏幕 用 法: int cprintf(const char *format[, argument, ...]); 4 t+ b) e( L# o6 i2 i' w# K( K程序例:

#include

int main(void) + |+ u( P3 E2 B3 B5 G7 u& s! s- Z( M{ /* 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 */ cprintf("Hello world\r\n");

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/* wait for a key */ ! l9 \# l" s' I7 T& G9 P; hgetch(); " f& w q, Q6 _* M0 e; H- }return 0; ' I1 A2 m. S& z \* z- ^6 H1 @} - A5 D* s! N9 @ " @( i2 `3 a- R! P1 }3 F/ f

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函数名: cputs ) E* F: q3 H- h% ?9 |; {) u; R功 能: 写字符到屏幕 - r n& {' B0 ~6 l用 法: void cputs(const char *string); 5 m2 W% I9 R! j+ J! X7 J8 a程序例:

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#include

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int main(void) { 6 [4 m* p" ?8 X/* clear the screen */ 2 L8 ~; Q. G7 G/ e6 Sclrscr();

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

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/* output some text in the window */ 6 L" T$ N, w1 d3 Y7 r* q( t+ M) jcputs("This is within the window\r\n");

/* wait for a key */ getch(); return 0; # i, W5 T0 U( A) p: c1 z( D} & }! y5 a) ^5 y' m % R5 o7 F# f+ ?! p

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); - C) j4 z& ]& @, l5 u* U2 E* R7 G程序例:

#include / o5 u, B) e: v6 W0 O#include 5 t6 H- q# i' [#include #include

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

/* change the default file mode from text to binary */ - Y$ j! ^% s# a% L8 m_fmode = O_BINARY;

/* create a binary file for reading and writing */ " _% w' W0 [, Bhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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/* write 10 bytes to the file */ write(handle, buf, strlen(buf));

/* close the file */ close(handle); return 0; }

函数名: creatnew 功 能: 创建一个新文件 , s5 ~/ s) j7 ^. d+ J+ R用 法: int creatnew(const char *filename, int attrib); ; `) l. S2 U: ~) i8 q程序例:

#include R0 {6 V9 q( h9 U0 y3 }# ?, m2 t6 ]#include #include ) ]5 d1 F3 a# U3 @' [* P#include #include

int main(void) { int handle; ) _8 A8 e7 a' V( k7 O: vchar buf[11] = "0123456789";

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

if (handle == -1) / b3 b9 H" o( m1 m0 G, pprintf("DUMMY.FIL already exists.\n"); 2 i% C$ R2 ~* n$ m0 c) Delse ( t6 J, j9 z3 R. h& a( @{ 5 E0 _2 |& M O2 X/ Bprintf("DUMMY.FIL successfully created.\n"); write(handle, buf, strlen(buf)); close(handle); 0 `8 v4 b# D! o0 h- ~/ N H} return 0; } 3 y8 G9 t, D/ Z- @" `- Y. w

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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 #include #include

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int main(void) { int handle; 0 Z3 T3 i n! w/ ]9 @6 ^% `2 X* l/ ]3 schar pathname[128];

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strcpy(pathname, "\\");

/* create a unique file in the root directory */ ' E* q3 {, g2 l: n( W) C1 R4 Uhandle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); " c! m1 s% ?, B* M. rclose(handle); 5 d6 V3 \0 v! W* n* W3 \% ureturn 0; } " \! Y4 V( v9 n0 |) {/ e / W6 s+ I1 \" l" G# t$ y# x3 R# F

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函数名: cscanf 功 能: 从控制台执行格式化输入 8 Q( p! x( T) K; ^% Z P& J用 法: int cscanf(char *format[,argument, ...]); 程序例:

#include

int main(void) { , m- o t L' O/ p5 W% F, _char string[80];

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/* clear the screen */ $ D$ _: `& j: r! L" mclrscr();

/* Prompt the user for input */ + K; \ ]2 |1 [ I+ z9 s1 hcprintf("Enter a string with no spaces:");

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/* read the input */ cscanf("%s", string);

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/* display what was read */ / ?( X F( T( E" Kcprintf("\r\nThe string entered is: %s", string); 0 x# g7 e8 h! s) L2 L$ treturn 0; _0 t+ j4 R# q* j7 p- j# j1 c2 ^}

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函数名: ctime ) ]) Y; o, f5 z! P- a' x功 能: 把日期和时间转换为字符串 P l( c* k% |- y0 d用 法: char *ctime(const time_t *time); 程序例:

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#include ! P8 Y: o" j, E: {8 S8 `#include

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int main(void) { time_t t;

time(&t); / Q" r$ L: y* I- G3 sprintf("Today's date and time: %s\n", ctime(&t)); l6 }" ?! i# I% i: rreturn 0; }

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函数名: ctrlbrk + H- L. B+ ^1 I, e功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); : I3 O, S; j5 r8 Y% [; B程序例:

#include 6 ]+ Q- A& {( m+ c7 Z#include

# a) a: S; d& ? M- v# n1 H

#define ABORT 0

int c_break(void) { 8 C' {! U! |- b) R8 a0 A Eprintf("Control-Break pressed. Program aborting ...\n"); : e5 t' d9 y$ Preturn (ABORT); }

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int main(void) # ?) o+ i" b( R* n2 q3 C( M2 x/ {{ ctrlbrk(c_break); " @9 G4 `% h$ e% u2 l! ?for(;;) { printf("Looping... Press to quit:\n"); } return 0; 0 p9 [" r$ W- O. c+ A1 v' b5 T}

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