函数大全(c开头)

韩冰

函数大全(c开头) 9 y+ y( V0 C }& u1 @, D

函数名: cabs 功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); 6 `- \; a- Z1 e* m' {6 |* F: D7 o程序例:

#include #include

int main(void) { struct complex z; & R9 c5 @' q. [* ^* Jdouble val;

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z.x = 2.0; % G6 w: ^& O6 ?5 i$ ]/ j% lz.y = 1.0; W: x$ x4 T& Y- Bval = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); + C2 j6 q) U/ t# |1 Areturn 0; + P% E3 {( c$ e6 Z( M} , ^ t- I& o+ \( j8 i2 V% _

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函数名: calloc % L( a: a( w4 p' w功 能: 分配主存储器 4 }2 A" Y0 f/ w. y0 S用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

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#include #include

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int main(void) / L* N' b4 Q9 G( i! q; w: L, a& I% I{ " u: S" r. m7 V$ {char *str = NULL;

/* allocate memory for string */ 1 h* z) T. _" f8 w! G4 M; dstr = calloc(10, sizeof(char));

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

/* display string */ 8 X6 M, h0 T9 G3 Q0 oprintf("String is %s\n", str);

/* free memory */ ' \8 _6 a! _. [) |free(str);

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return 0; : Z4 z! `2 O' k/ ^' ]' [9 j( c} ' _ h0 @2 M, ^4 R/ i& t/ Z* P( w 0 P9 K- W$ a6 X9 P

函数名: ceil 功 能: 向上舍入 , Y! _9 M( s1 n用 法: double ceil(double x); 9 T; R6 D) U' t+ L, O: t程序例:

#include #include

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int main(void) % A6 D3 C1 e6 n% w; w& ~{ 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); printf("number rounded up %5.2lf\n", up);

return 0; } : k( H3 E) k0 a. x ; w% B% @! ]& P8 i5 E; D ! k& A1 \- r+ t4 O: m

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函数名: cgets 2 j% b$ f$ y# q功 能: 从控制台读字符串 用 法: char *cgets(char *str); : T! l- ?# ]4 y程序例:

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#include #include

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int main(void) { $ D) s r+ e( M. E2 `3 c9 _char buffer[83]; ; y2 B- M0 u) schar *p;

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/* There's space for 80 characters plus the NULL terminator */ 6 S2 X" N" S* P4 I0 xbuffer[0] = 81;

printf("Input some chars:"); p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); " w3 {6 a( y1 a; O6 \% kprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer);

/* Leave room for 5 characters plus the NULL terminator */ ! Y) g- s9 D% B: k5 x( F* u% Nbuffer[0] = 6;

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); return 0; } ) M' a7 h' a; ?

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函数名: chdir 功 能: 改变工作目录 用 法: int chdir(const char *path); 8 \! h" x8 O1 _3 X1 X# B程序例:

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#include 1 W5 W/ O7 [" [1 ?! |#include ( ]7 Z9 W$ {# p6 l" ^% f0 d% a- m#include

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

int main(void) ' a k# r* e! d5 V$ S0 ` A4 u{ if (getcurdir(0, old_dir)) { perror("getcurdir()"); 9 n. m( ?% \! q4 O# |. g+ Y7 a* Kexit(1); } 7 o/ E* t8 L. T5 y1 r D# Mprintf("Current directory is: \\%s\n", old_dir);

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if (chdir("\\")) { perror("chdir()"); , b% z" n k/ f5 [. M p% Yexit(1); - {1 z% K! [ t: Q}

if (getcurdir(0, new_dir)) : x! g8 b+ ?$ V9 f5 F{ perror("getcurdir()"); exit(1); } # u3 J, B1 F* k. vprintf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); * s. f% K9 x% N* e7 Eif (chdir(old_dir)) { - h" m A# h6 j, Y6 p) G- @0 \perror("chdir()"); . S/ X6 t ^ G3 ]4 _4 pexit(1); }

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return 0; ' }) p0 w1 \5 ]9 K- Y}

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:

#include $ G) U' D3 W4 p6 @5 D#include #include

void make_read_only(char *filename);

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int main(void) # O$ J0 N$ D" Y0 p{ # i, s! T& ~" z2 H4 w4 umake_read_only("NOTEXIST.FIL"); 2 k& i$ H F4 T, t' Vmake_read_only("MYFILE.FIL"); ) q" t0 q r" z; I# Nreturn 0; : f3 H$ }3 ]1 f7 k" M- I1 x}

void make_read_only(char *filename) { int stat;

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stat = chmod(filename, S_IREAD); if (stat) 6 o4 O' X$ o* |- Eprintf("Couldn't make %s read-only\n", filename); 2 z) }- Y; I+ I% Delse % ^$ \0 y7 b2 S# ^5 ?: {! gprintf("Made %s read-only\n", filename); } 1 {) ` E7 ^2 u * V1 r5 S8 u" S

函数名: chsize 功 能: 改变文件大小 用 法: int chsize(int handle, long size); 程序例:

#include #include 4 C/ i3 S$ p- l#include

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

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/* create text file containing 10 bytes */ . f2 ~/ n. Q" X) U$ {- Mhandle = 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); ; c9 D- e# O9 G& l& Q7 wreturn 0; # L$ P @; v. p5 P' e} 6 e8 }6 }7 ]' q8 ~6 F) V6 ?: Q& ^

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函数名: circle 功 能: 在给定半径以(x, y)为圆心画圆 2 r# l0 O, i7 d& V用 法: void far circle(int x, int y, int radius); 1 [% v' f( s: l9 G( |程序例:

#include #include + T8 _. j6 a+ m/ q0 @. X; s, b#include 6 O8 G; W; \* ]: a. d* M#include

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int main(void) % @+ d# I4 ?! Q' M: `{ 0 u/ n# E0 j5 @# u" N5 E0 Q/* request auto detection */ int gdriver = DETECT, gmode, errorcode; + K p5 k) ^ L: Aint midx, midy; int radius = 100;

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

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/* read result of initialization */ # c+ s j$ o; S/ S; ?* d% Kerrorcode = graphresult(); $ B6 q- K# e$ |3 tif (errorcode != grOk) /* an error occurred */ 0 a U- o* R' }% B" S5 b) B{ : \% U1 t% v6 m( D; V* n. Lprintf("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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/* draw the circle */ 8 i- t( T5 f3 I9 g! c1 L$ wcircle(midx, midy, radius);

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/* clean up */ getch(); closegraph(); return 0; } * `# z* _/ r3 H ' v& s; h; Y6 i/ E8 d% }# K0 X

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函数名: cleardevice 功 能: 清除图形屏幕 用 法: void far cleardevice(void); 3 ]2 T8 Q3 k" i) c6 @1 ^) A$ F程序例:

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#include #include #include ! I8 a0 M& E, g0 @ X* Z#include

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int main(void) { /* request auto detection */ - _) d# u6 ~- E4 p% wint gdriver = DETECT, gmode, errorcode; 8 F0 w, B4 T- J [7 ]7 k! Y K$ Rint midx, midy;

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

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/* read result of initialization */ errorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); 2 M: k. T9 C+ \" G0 hprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 4 q4 r4 m6 T' |; }9 P}

midx = getmaxx() / 2; midy = getmaxy() / 2; . B$ {9 k" h" g+ L$ k0 Qsetcolor(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 */ . f, A8 d9 m: [& ?% O: D8 t5 e, Ygetch();

/* clear the screen */ cleardevice();

/* output another message */ % d x2 T: j. K% C0 H B3 _: gouttextxy(midx, midy, "press any key to quit:");

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/* clean up */ 1 g9 s' e7 j& n9 G( \getch(); 5 ~! Z& a% x9 h- [- {9 [closegraph(); 7 A$ z- q$ l0 h* l1 E$ Q/ Kreturn 0; 7 V D. {. \. w8 ?" y9 n} $ N9 `: A' B8 r% N: O2 {& ~ 8 p! L% N; J' q& G" X/ ] 3 i) M1 l' p6 {

函数名: clearerr # e. H' L- t; ^/ V: k功 能: 复位错误标志 3 I, ^$ Q8 {; h用 法:void clearerr(FILE *stream); 3 W1 n2 m9 v4 N3 h* E! Z( @) F程序例:

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#include

int main(void) { FILE *fp; ! G8 N3 J- W& z% T3 h0 N3 Qchar 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 */ ch = fgetc(fp); printf("%c\n",ch);

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

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

fclose(fp); return 0; : A/ ^$ Y+ d% M! p! e- S2 C, k}

函数名: clearviewport 功 能: 清除图形视区 ' k1 E7 \4 V e5 G+ e7 d: o用 法: void far clearviewport(void); 程序例:

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#include #include #include #include

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

int main(void) { /* request auto detection */ d1 R1 V9 q$ I) T. K$ P5 cint gdriver = DETECT, gmode, errorcode; int ht;

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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 */ + r3 O- I4 U6 E# g( E9 X |9 Z{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); * l; `: A0 Q+ x) t+ `( q3 M& cexit(1); /* terminate with an error code */ }

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

/* message in default full-screen viewport */ 7 z) t. W+ h% Xouttextxy(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 */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 6 |9 ~) z: O) houttextxy(0, 2*ht, "Press any key to clear viewport:");

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

/* clear the viewport */ clearviewport();

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

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/* clean up */ getch(); ' ]/ J( O# V9 n' X4 c5 q0 {1 \) Wclosegraph(); 1 m& L7 }3 O& w# p: @return 0; $ S/ ^. r r. J1 N} 5 x; R# N' v/ S5 H2 b, c/ H 3 x0 T9 q. n' w: C) y

函数名: _close, close 功 能: 关闭文件句柄 & C" s6 `# e+ a& V3 G8 x/ B+ m用 法: int close(int handle); 程序例:

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#include #include % K4 ~4 ^! c" Q7 o& o* X% }#include # R( a2 \ n' s2 T+ G+ I#include

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main() { ' o/ v, ?) x7 _- l* zint handle; char buf[11] = "0123456789";

/* create a file containing 10 bytes */ handle = open("NEW.FIL", O_CREAT); 5 g- L6 ^4 c" P- `. {( Hif (handle > -1) { write(handle, buf, strlen(buf));

/* close the file */ : ~" z$ ^3 v" [5 X1 u( ]7 V& v; Qclose(handle); } else 0 x& J5 H- F3 J, D{ 6 M0 D7 d% e) ?- s' N0 jprintf("Error opening file\n"); } return 0; # z- p. U* a b# @3 z} + Y% j9 M4 `- o6 a & t! w; J- I/ _ A$ c+ y

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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:

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#include #include 1 i5 Y% D. M8 ]2 a; O7 A+ q8 f- k% G#include

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int main(void) - E3 ?2 N6 E6 O% n{ clock_t start, end; start = clock();

delay(2000);

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

return 0; } 8 i( `- o `! T3 s0 C; Y0 p" `, n 7 G$ D9 Q. P5 ?: ~4 W

函数名: closegraph : P7 Q3 M$ A6 c- B: m9 d功 能: 关闭图形系统 用 法: void far closegraph(void); # ~3 P/ B0 Y0 X9 w) e q5 O程序例:

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#include #include #include , I0 o5 r# _) Y#include

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int main(void) 4 ]2 T; C Y# Q$ S" h: e) A% r! H{ /* 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();

if (errorcode != grOk) /* an error occurred */ 2 \, q/ Q) z! ]. Y{ printf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 8 T, W! g T4 C- ^" j8 a}

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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:");

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/* wait for a key */ " f" Q& D" [& Q* E* Ogetch();

/* closes down the graphics system */ ! V T5 [2 m% ~$ N5 Z' vclosegraph();

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printf("We're now back in text mode.\n"); printf("Press any key to halt:"); getch(); return 0; 3 v1 Q3 d+ Q/ M* A5 f9 n; |5 p4 P} 1 G! J$ Y* R1 {; w) I

函数名: clreol 0 Z+ d, k; X+ S0 |4 O9 G; |( ~功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 1 i8 p4 T8 F2 i程序例:

#include

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int main(void)

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{ 7 Q4 t8 U& h5 J7 _clrscr(); ! a. `1 @; f9 b% o# fcprintf("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"); @7 B9 B& W2 a# j9 Q# hcprintf("Press any key to continue . . ."); gotoxy(14, 4); 5 A! S& b* w8 d$ j; |7 h8 dgetch();

clreol(); getch();

return 0; 8 L, V+ Z# Y9 k+ m9 g* Z1 O} 1 G/ i# }$ b0 j' W+ g, U 8 @0 _6 p }) J. C3 O8 }+ A6 ~ 1 W w! t' h u6 N1 `. m

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函数名: clrscr 功 能: 清除文本模式窗口 用 法: void clrscr(void); 程序例:

#include

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int main(void) 3 a$ D' S7 U5 H{ int i;

clrscr(); for (i = 0; i < 20; i++) cprintf("%d\r\n", i); : A( V. i9 a' f4 y9 {cprintf("\r\nPress any key to clear screen"); getch();

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clrscr(); + l, M% E5 U- t" \' E, Ocprintf("The screen has been cleared!"); ! d( p! a' ?( ]$ t1 Ygetch();

return 0; } & M0 D- [/ T a6 ~" _9 Q 5 X5 s/ [( K( ]* h. ^- q: S

函数名: coreleft 4 o; t9 ^& [9 D, m功 能: 返回未使用内存的大小 % w' V6 P3 M- ?' x用 法: unsigned coreleft(void); 程序例:

#include #include

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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());

return 0; }

函数名: cos 功 能: 余弦函数 1 x' N r4 J* f) }3 h9 S用 法: double cos(double x); 4 K6 y' k' G' Y! G' F程序例:

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#include #include

int main(void) 5 l V( g% N" r8 N; k; E) {{ 2 m1 Q8 Z% z5 f( Z4 \3 gdouble result; ' Z8 e& H% G' X) mdouble x = 0.5;

result = cos(x); ; X$ o" a5 |! ^1 Y1 wprintf("The cosine of %lf is %lf\n", x, result); return 0; } , Q2 I' U5 I; r2 P $ b+ `# b1 j( P2 h- I2 F

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函数名: cosh * `9 x8 v( I# x' s. H功 能: 双曲余弦函数 # S( x, k @0 r4 Y$ b6 ]用 法: dluble cosh(double x); 1 R2 K& k6 p& @: U8 Y% w$ U程序例:

#include ) N" A" A" N9 a7 [/ `7 E9 E) F g#include

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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; ) f) `& V: s4 V}

函数名: country 功 能: 返回与国家有关的信息 ' a/ a/ B9 P* M t% t9 ?用 法: struct COUNTRY *country(int countrycode, struct country *country); ( X: {, |. M/ I2 d9 h" k- c+ {程序例:

#include #include

#define USA 0

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int main(void) ; b6 K* e5 q' @8 ?1 Z# ^* T$ F{ 9 o \# i: Q8 }9 i# e& @struct COUNTRY country_info;

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country(USA, &country_info); printf("The currency symbol for the USA is: %s\n", country_info.co_curr); + u5 K6 b* L4 C! a9 S5 Greturn 0; / _2 ?! B/ A3 O5 l7 s; P, X) s} . X9 B+ `3 X- L' H' Q6 T % o1 U2 ^& @3 ~$ ^# T

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函数名: cprintf 6 m% z: w' {7 x! j0 @功 能: 送格式化输出至屏幕 2 u3 G i2 g/ Y& G5 J- q用 法: int cprintf(const char *format[, argument, ...]); , v1 I' H" p" g4 y程序例:

#include

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int main(void) { /* clear the screen */ ( Y+ a% a+ {+ nclrscr();

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

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/* output some text in the window */ & N4 B" K7 `- p) p' hcprintf("Hello world\r\n");

/* wait for a key */ getch(); # M% t+ @, q ]+ Rreturn 0; } 9 O- S, ]5 w' d/ W 9 z. e4 h3 @4 T4 s0 W% I `, @: q1 Y! s

函数名: cputs 功 能: 写字符到屏幕 用 法: void cputs(const char *string); & x/ A# k H/ W' h* g程序例:

#include

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int main(void) : \1 q& P; S+ J4 Y; w! S{ 3 g* I$ p: S i! x( L& X- s. B( }/* clear the screen */ " }+ ]5 {! ?) u9 X2 G \, q" dclrscr();

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

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

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/* wait for a key */ 3 W; ~' k+ A8 Y% \! r) egetch(); return 0; 5 I( k, G% y. j: V2 T0 S} # x( W4 I$ Q% x# w& l1 o 6 o! `* k9 f& {- | N

函数名: _creat creat 2 E; k3 ^4 \/ g8 c3 I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); ( G, b r6 H/ I- ~5 Q程序例:

#include 8 I Y5 B. t0 F1 s7 p- l4 @#include #include ) k$ h( f# z; N. d1 i. A#include

int main(void) + D5 M7 N' A6 Q- r{ int handle; 0 u0 ^0 g# ?! N2 Z) [) ?* `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 */ ; ^) g$ |* V( Ghandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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

/* close the file */ 0 ~ }5 @3 T3 L+ O. Zclose(handle); ' {0 b+ ^# g' V( \1 f, Breturn 0; * g/ v. H6 e6 [( T( r} ( I) b3 s) x4 w8 `

函数名: creatnew 5 I( f' X& p: l: S功 能: 创建一个新文件 用 法: int creatnew(const char *filename, int attrib); 程序例:

#include #include #include #include #include

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) & W7 G4 l' Q( m/ J! }printf("DUMMY.FIL already exists.\n"); 5 I; I- q6 d; z. T8 kelse B4 N+ Z% g8 N- Z/ h( a) ^* j{ printf("DUMMY.FIL successfully created.\n"); 6 K0 E: H/ L& v$ iwrite(handle, buf, strlen(buf)); close(handle); } + F ~8 b: ?: {" w7 Mreturn 0; # b3 i2 U1 Z/ y% A0 [; ^}

函数名: creattemp 7 p- z0 p/ E% m$ | a Y4 n功 能: 创建一个新文件或重写一个已存在的文件 ! i. N5 O+ x- V# \: M0 I用 法: int creattemp(const char *filename, int attrib); 程序例:

#include * t$ X5 P, K/ q5 R. W4 Y) }#include #include

int main(void) { ! ?6 U8 a, s; g. Q- Gint handle; 3 A( z4 m( R4 Schar pathname[128];

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strcpy(pathname, "\\");

/* create a unique file in the root directory */ : F) q4 A, |2 J ]. F7 g1 F. `& x7 Chandle = creattemp(pathname, 0);

printf("%s was the unique file created.\n", pathname); close(handle); return 0; } ' `! W. ^ U2 q) c" t3 { % _; q1 p4 s- }6 }' U9 v

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函数名: cscanf w" Q3 R; v( _; O功 能: 从控制台执行格式化输入 用 法: int cscanf(char *format[,argument, ...]); 8 D1 N( d2 C1 }; J程序例:

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#include

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int main(void) { char string[80];

/* clear the screen */ clrscr();

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

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

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/* display what was read */ 2 U7 ]' Z8 {( X& \% \: Xcprintf("\r\nThe string entered is: %s", string); q2 k' U& J W4 lreturn 0; 4 V7 H5 V. v1 ^/ k& [} 3 n/ R) o: s* F0 |! o 8 p0 s& S5 D; k# [4 u* D) {

函数名: ctime 功 能: 把日期和时间转换为字符串 % m1 E& r8 ?' o/ d* O5 ~用 法: char *ctime(const time_t *time); # O2 E0 ^, T. J1 F# m, `3 J程序例:

#include 1 \2 z$ Z* U0 m7 [/ W9 s#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)); ) l8 _- G! @$ w9 K# a, creturn 0; } 2 T8 Q2 V& S" q. A 9 |1 | j! n. e* n

函数名: ctrlbrk * [; Q( L9 {' F c8 ~功 能: 设置Ctrl-Break处理程序 8 U5 B4 `9 g# l7 J' A$ G用 法: void ctrlbrk(*fptr)(void); 程序例:

#include ; I& j; A! v% x7 }5 \( m6 g) L7 c#include

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#define ABORT 0

int c_break(void) g4 W" F _9 @{ 1 H# q! _+ J! k6 I4 Xprintf("Control-Break pressed. Program aborting ...\n"); . c, d- T1 `1 D" c/ a7 `return (ABORT); / D \- i0 F G+ E# ]8 V}

int main(void) ! b% e: C5 p. C8 H. q9 d) ^1 {{ ctrlbrk(c_break); for(;;) { printf("Looping... Press to quit:\n"); 2 Q/ z/ d9 n" y4 X; W3 s1 q4 C( p$ ?$ V} 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