函数大全(c开头)

韩冰

函数大全(c开头)

函数名: cabs ! v/ X% P# t" F2 F; l功 能: 计算复数的绝对值 用 法: double cabs(struct complex z); # R* Z. o; b8 N$ Y程序例:

7 r; J, ]: ]2 [

#include #include

/ z" u: b0 c) i P' \

int main(void) 4 {- `$ I: H I1 }" w{ struct complex z; double val;

z.x = 2.0; u( F8 h8 [( z* e/ b. C' }( Lz.y = 1.0; val = cabs(z);

printf("The absolute value of %.2lfi %.2lfj is %.2lf", z.x, z.y, val); return 0; } 4 @( J2 P! c, }, p

函数名: calloc 功 能: 分配主存储器 ( x: \* G: J) p0 l" b6 K用 法: void *calloc(size_t nelem, size_t elsize); 程序例:

#include #include

5 I& N7 B+ A, D) Y

int main(void) % j. E T+ Q% \8 ~, r; C6 g3 f1 [{ * w4 D6 }! o9 ^4 A6 T) Bchar *str = NULL;

/* allocate memory for string */ str = calloc(10, sizeof(char));

5 N. j( ~7 I/ M1 F$ ?! o

/* copy "Hello" into string */ # V* i3 C( `, J: b, @- _! z: ~- Q3 bstrcpy(str, "Hello");

3 h5 B) N/ f! h4 o

/* display string */ " \4 z+ B, O. f+ y( d: U/ ^1 X- y; Hprintf("String is %s\n", str);

/* free memory */ 9 j5 ]1 p( g0 n7 i' \+ U( v# ffree(str);

return 0; 8 x. X. g( m N} 6 Z4 T5 s9 |7 n* Z3 i2 u

! A7 [5 p" X4 W& M! q7 P

函数名: ceil 功 能: 向上舍入 5 ^ H* O9 i6 b' K& Z1 N) ?用 法: double ceil(double x); 程序例:

#include 7 f9 G; T# W% \/ Z' C0 K#include

( y% P( \1 y$ j3 t, y+ H' j3 E7 C

int main(void) 7 {9 V9 ]4 { W& E. F) p{ double number = 123.54; / {& S* `: \' a3 P3 f. n) ^, ddouble down, up;

0 K2 H/ m: f. h4 s

down = floor(number); 0 u, @# |1 e4 Gup = ceil(number);

! e: x1 Z( P+ [5 j" r

printf("original number %5.2lf\n", number); printf("number rounded down %5.2lf\n", down); 6 `$ ~ I+ X3 r+ Wprintf("number rounded up %5.2lf\n", up);

- ?5 ?% C& d: [" e* {! j9 ^. ~) }6 J

return 0; } 2 [7 `9 k1 Q" G+ ?. ]0 Y7 E2 V . B: E- n. U; R- |) }3 Q# e t

函数名: cgets ' _5 }% _! Y4 p% i3 N0 C) M功 能: 从控制台读字符串 r& |8 p9 u9 _用 法: char *cgets(char *str); 0 ^. y' V1 a8 \- t程序例:

' ~1 ?9 k$ O' ~

#include #include

int main(void) { 2 Q5 ^, e2 z9 d+ m" wchar buffer[83]; + _+ p+ [8 z2 c% e. ~char *p;

/* There's space for 80 characters plus the NULL terminator */ buffer[0] = 81;

+ z# [0 N2 [- k" [" m' k

printf("Input some chars:"); 9 p, {: a- n6 {p = cgets(buffer); printf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); ! P& m! h7 X9 p+ {4 W. o4 V) w4 Uprintf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer);

/* Leave room for 5 characters plus the NULL terminator */ 9 i/ {+ R: }7 U, vbuffer[0] = 6;

$ Y& V5 X& l9 o1 ~4 u

printf("Input some chars:"); p = cgets(buffer); ' E0 f+ [& f/ E& rprintf("\ncgets read %d characters: \"%s\"\n", buffer[1], p); 3 h0 m g8 M& ~) }5 O/ ?printf("The returned pointer is %p, buffer[0] is at %p\n", p, &buffer); . }8 }" i" V2 _; N2 `, xreturn 0; } ' d0 \- ~2 m" s 8 }' H3 Z9 |6 c

1 ?: g& e" m% h9 _5 `5 c8 `9 A

函数名: chdir ( g, [2 k4 Z" p; m% L. }! n v/ ]功 能: 改变工作目录 " I# |8 U' N2 h# B6 r8 c用 法: int chdir(const char *path); 0 U& S! h3 T6 V* w! @/ H程序例:

; o$ f0 p4 V3 J! o: T

#include #include #include

5 z% \8 Y3 s4 z6 h

char old_dir[MAXDIR]; / y. F" z5 l1 x& a; `1 mchar new_dir[MAXDIR];

int main(void) { if (getcurdir(0, old_dir)) { 8 V& X8 z9 G7 _ L3 ~perror("getcurdir()"); 8 G' t* @0 {; W% fexit(1); } / h9 e& M- T1 k/ |0 |. D% s7 I: G) Jprintf("Current directory is: \\%s\n", old_dir);

2 \, m0 E) z% _# i) u# R" i. Q

if (chdir("\\")) { # c- E, [6 {( ^perror("chdir()"); 6 O% P2 W6 K3 y9 W D. y9 [exit(1); % a: v% ]; |1 ~}

2 d4 u% A @1 X# Z) _

if (getcurdir(0, new_dir)) { perror("getcurdir()"); exit(1); 2 M, S8 {, p2 Z9 R! u} printf("Current directory is now: \\%s\n", new_dir);

printf("\nChanging back to orignal directory: \\%s\n", old_dir); if (chdir(old_dir)) { perror("chdir()"); exit(1); }

return 0; } 8 S3 ?; {) S7 y: { d% P 7 O$ ^: I. q1 i

函数名: _chmod, chmod ; `; A/ z3 D) r( g功 能: 改变文件的访问方式 + e4 p5 x- w/ t& k4 p( A6 [0 Z/ z用 法: int chmod(const char *filename, int permiss); - a8 _! r, L6 i" M3 t9 R程序例:

# z5 h. t6 Q U7 K

#include #include 3 U) w6 n8 X' D B/ ?0 y; A#include

$ y' ^1 S8 O0 D9 n

void make_read_only(char *filename);

/ q: m& n3 C, `7 } c0 d0 Q

int main(void) 9 E+ D' R. n7 s0 M$ d* v{ make_read_only("NOTEXIST.FIL"); & w2 t- a; d2 d6 F6 Gmake_read_only("MYFILE.FIL"); ?% v6 {% X/ _! t- K. {: {3 Hreturn 0; }

7 |" h: S& }1 Y( C% V

void make_read_only(char *filename) & t3 W! l8 s8 I( U{ 4 u5 y. e9 q! x0 R9 n# ]int stat;

# L3 y: D- Z- H# r% }& |. _% k

stat = chmod(filename, S_IREAD); if (stat) printf("Couldn't make %s read-only\n", filename); - s+ }9 b, c& Z0 {1 H( z/ w! o' Nelse printf("Made %s read-only\n", filename); } , V4 s- h8 ]5 P

- E& b5 S8 |( ~0 x7 b! @; l

函数名: chsize 功 能: 改变文件大小 用 法: int chsize(int handle, long size); ; p$ ^% M. S0 W1 i程序例:

3 J1 w9 W1 Q( a8 A" e

#include ' ?( f& P+ t, R* y* Z( |' K#include ' v$ n& Q/ g3 U8 s q. S9 z7 g#include

int main(void) 7 I) _ X9 M: l3 ?$ |; c7 t% A{ # @* s: R& d+ Z/ @+ n5 a* {1 \int handle; 8 R$ L, Q2 U- L" p3 v- Achar buf[11] = "0123456789";

6 X+ e7 I+ l) u3 Y# s

/* create text file containing 10 bytes */ 1 G' y- r6 Q( r! I0 B9 whandle = open("DUMMY.FIL", O_CREAT); $ x, K/ }: T% V0 C! q2 lwrite(handle, buf, strlen(buf));

2 d1 M# \7 c! c$ K" N$ Q5 k

/* truncate the file to 5 bytes in size */ 4 f0 f1 I" ^4 F' Gchsize(handle, 5);

/* close the file */ & {* x1 e, v( q$ rclose(handle); / K% v( j# y& G0 Nreturn 0; } ) q- s, V H( U+ Q' M. R% K" w 5 Q) Z2 e' h( ~ ?! b1 ^/ o

; J0 X7 D& k9 |" }

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); 程序例:

#include #include #include #include

3 g, H5 i6 I/ ^; w" h

int main(void) { /* request auto detection */ int gdriver = DETECT, gmode, errorcode; / K( ~) P: Y' D! E, aint midx, midy; int radius = 100;

+ x2 o; ?# e/ I2 T' l7 D

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

/* read result of initialization */ errorcode = graphresult(); + T( u) `7 P4 |3 S8 q1 Mif (errorcode != grOk) /* an error occurred */ { printf("Graphics error: %s\n", grapherrormsg(errorcode)); % w6 ]# ^0 `( L0 D/ D$ j( Aprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ 8 l9 L. t2 O, I( p" i! B# r4 C}

5 j/ N% Q0 O! @; c

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

/* draw the circle */ 2 G7 S* O" Z$ ~; c" @! icircle(midx, midy, radius);

/* clean up */ , K1 ~' j; X2 m, b) Z+ v1 ~$ rgetch(); closegraph(); return 0; 5 d4 {. G$ \# G* V$ p1 S5 D} * q" X4 t/ b4 ^ m2 N' B" y" T % g! W/ X h+ l2 j

- G6 Y- v" m6 t' }) N7 T% \; E

函数名: cleardevice 2 f% m% b1 v0 b( [3 @& M0 e. d功 能: 清除图形屏幕 7 T" R3 c6 H( S: m; ]用 法: void far cleardevice(void); 程序例:

#include #include #include #include

% N9 w2 s! @4 I# Z2 X

int main(void) { /* request auto detection */ , B' u a, ]% O. K/ Z) R8 M8 c3 Y9 ^int gdriver = DETECT, gmode, errorcode; int midx, midy;

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

/* read result of initialization */ ' D; F1 }, z Y: Q1 @2 jerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ 6 m% Q: ~3 L" K{ 9 \& k( g- x, z2 b; Z) dprintf("Graphics error: %s\n", grapherrormsg(errorcode)); & C: r. d z2 f2 G1 t+ l6 ?printf("Press any key to halt:"); 7 @* X7 T% i$ L: {: ugetch(); exit(1); /* terminate with an error code */ }

$ p7 ^1 p' W9 p" y/ J% B- |9 o' |

midx = getmaxx() / 2; - C7 \. f6 e# l) lmidy = getmaxy() / 2; setcolor(getmaxcolor());

2 q3 [% a0 D# c& ^9 u( q& L

/* for centering screen messages */ : s6 r* r8 S3 `4 e# O( Hsettextjustify(CENTER_TEXT, CENTER_TEXT);

/* output a message to the screen */ outtextxy(midx, midy, "press any key to clear the screen:");

7 c% p% Y, T1 H2 _* i. b

/* wait for a key */ 4 z% g' s8 K/ \3 @# u2 m9 u* O4 zgetch();

" H9 j6 I' H& [' h% ]; A

/* clear the screen */ " [7 c+ i. X7 d, x6 Bcleardevice();

" Z; U& o- M' m' J3 `9 K- ^

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

( d" V. F- E @6 B2 i+ u$ N

/* clean up */ ; Y) [% x/ ~( h+ ^2 }* s8 [4 ggetch(); closegraph(); $ M9 O% v: J9 {return 0; } 6 k6 E! M$ G6 j+ V9 P3 Z 6 P( D7 e7 M* Z& ]% V6 w' L

$ ~7 p4 j5 U3 M* C6 d8 g' I$ o

函数名: clearerr 功 能: 复位错误标志 6 e+ ?! m- ~& z* o用 法:void clearerr(FILE *stream); " O q t1 J/ c) d程序例:

#include

, k" d5 t% p1 `2 h2 ~) n

int main(void) ( U% s+ [' C/ ~{ FILE *fp; + |+ c8 D' U F x/ u8 zchar ch;

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

/* force an error condition by attempting to read */ ch = fgetc(fp); 3 b$ ]. ]8 P, H6 _printf("%c\n",ch);

* }# d) V+ n) }) \1 R& T4 H$ m' @

if (ferror(fp)) 6 ?8 p* U# ?' L: K% |- D{ ; q7 Q' i6 X! H! ^# I+ e6 \/* display an error message */ printf("Error reading from DUMMY.FIL\n");

8 [5 R1 Y/ o, n$ l4 S4 L

/* reset the error and EOF indicators */ clearerr(fp); - F9 h6 U/ }% R}

4 E: I/ Q3 d! e4 n8 l* d

fclose(fp); return 0; - L- G, v1 s- ~; }6 `$ ^- R} - f7 a4 ~* ~- ^. p# @% A* g $ |$ e$ f* P8 X4 D# i5 Y; N . @4 K( p9 F4 S" ~- C0 I. n

* P7 Q) a* A1 ~: o

函数名: clearviewport 功 能: 清除图形视区 . g: s1 D/ k3 W. Y7 Y1 ?用 法: void far clearviewport(void); 程序例:

8 P. x0 I# K' L( y: h' r

#include ! J0 v: ^2 C2 \4 x% K+ N/ N0 T q#include 0 O* b: F7 [( @, o. E, x8 G- i# x#include #include

3 I# n9 U9 t$ W+ _7 \, [+ c

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

int main(void) { /* request auto detection */ - q/ G% \; P+ a. K0 q, uint gdriver = DETECT, gmode, errorcode; int ht;

/* initialize graphics and local variables */ ; W/ F( B) [& E! s3 yinitgraph(&gdriver, &gmode, "");

/* read result of initialization */ ; A5 d2 B3 }. f, Xerrorcode = graphresult(); if (errorcode != grOk) /* an error occurred */ { % f! N- u; U; y3 A+ S( {( ]printf("Graphics error: %s\n", grapherrormsg(errorcode)); + P$ O( h: u# B9 B) Jprintf("Press any key to halt:"); getch(); exit(1); /* terminate with an error code */ ! y# m0 P% j0 u" k& I- H}

9 H6 Q7 I" F& ?8 B2 W+ i( c1 x

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

. Q& A1 `( [0 i s" a

/* message in default full-screen viewport */ J) O* H v4 I4 |0 eouttextxy(0, 0, "* <-- (0, 0) in default viewport");

/* create a smaller viewport */ 8 o4 G8 Y0 S: vsetviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON);

; ?6 b4 u* g. n" [: j

/* display some messages */ outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); outtextxy(0, 2*ht, "Press any key to clear viewport:");

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

/ q5 a7 q& k( t# H% J- ]0 G

/* clear the viewport */ - m, o* N% p. u, s/ U( Tclearviewport();

/* output another message */ & p$ V2 b1 K% V. v/ jouttextxy(0, 0, "Press any key to quit:");

/* clean up */ 0 L0 e, Z6 a8 f+ Ugetch(); closegraph(); % D+ h: h7 s8 yreturn 0; }

3 U2 d9 _2 u7 L! O! P5 u

函数名: _close, close , D. L; m2 D3 o功 能: 关闭文件句柄 用 法: int close(int handle); " p) t ]# r! ^) g程序例:

, X- i5 L7 O# Z1 S& N+ W" ^

#include , q& k" u5 ]( s0 K; N' T& c#include # S% Z& Y! u- d, ]: _#include #include

main() $ d+ l5 W0 ]# ?9 A* H! o{ 0 Y. |4 K* q% F2 F% Rint handle; char buf[11] = "0123456789";

+ T0 _( v9 D# z [# `$ p

/* create a file containing 10 bytes */ / r& v( r7 l3 ?4 ^' C( Thandle = open("NEW.FIL", O_CREAT); 3 a6 H; N0 n# h' hif (handle > -1) # [& \* A, Q: w2 I2 R3 y, j* c4 n{ # h! B3 Y" {6 R1 H# p9 b" Jwrite(handle, buf, strlen(buf));

y# y+ V* l$ M$ m# t: D

/* close the file */ $ K/ e3 k/ l- j }/ `close(handle); } else : S5 e9 l7 |5 P2 z{ ) A( q0 c: r Gprintf("Error opening file\n"); ! T/ t. x4 p) C; O5 [% I& V6 s} return 0; ; |5 K$ l8 X1 `; j( Q& O} 4 n2 f9 o) B, R" J* \8 p 9 R2 K8 G: {' G( N2 f

函数名: clock 功 能: 确定处理器时间 用 法: clock_t clock(void); 8 T, R. W4 A; w: L- j7 i6 i程序例:

#include ' |# v7 |; `! ~( P6 N1 u/ w* g% s#include #include

! t6 X6 o% R9 p' N- q- ~. G

int main(void) { e% }: K+ W; Kclock_t start, end; 9 n$ e3 f% D6 wstart = clock();

+ y! ~& ]( B+ m9 w/ I- {6 p* F. L

delay(2000);

end = clock(); . P6 I/ g; c' Fprintf("The time was: %f\n", (end - start) / CLK_TCK);

return 0; } 9 y$ s# u) G9 ^" c0 C9 I0 H , N7 @. E" A2 {! S

函数名: closegraph 功 能: 关闭图形系统 - P4 T4 B) U0 B6 D/ w4 w用 法: void far closegraph(void); 6 p5 Z( C: J8 ]4 L程序例:

f/ ~0 m% H3 ]. j9 q

#include & B5 e. p, Y( m W) P: ^. z% O4 k#include #include ; u' Y0 w" G9 Z6 g, F. x) ~3 N#include

# d. c4 h5 q y( v+ e

int main(void) { " z, l0 d5 z* h# z* J/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int x, y;

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

' I$ b D$ m% e" g" W6 s

/* read result of initialization */ errorcode = graphresult();

if (errorcode != grOk) /* an error l) k M+ s, u$ B( soccurred */ { 6 c. y' c+ `. Tprintf("Graphics error: %s\n", grapherrormsg(errorcode)); printf("Press any key to halt:"); ; L: S6 u9 f6 egetch(); 7 j* v' l- G2 h) r& j, ]! Jexit(1); /* terminate with an error code */ $ P) d4 B3 e! k. b. ^5 r}

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

* g6 d$ Q% u# Z9 m5 k8 u1 M

/* output a message */ settextjustify(CENTER_TEXT, CENTER_TEXT); 1 z3 z+ C$ |; @outtextxy(x, y, "Press a key to close the graphics system:");

: {" d) i r- F" V

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

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

printf("We're now back in text mode.\n"); printf("Press any key to halt:"); / X4 p4 ^" O" h/ Q7 s Bgetch(); 7 Z0 p/ Y- F0 P. \4 Treturn 0; }

, ^, @, X6 C9 X2 H

函数名: clreol 功 能: 在文本窗口中清除字符到行末 用 法: void clreol(void); 程序例:

#include

int main(void)

! H1 f4 [0 Q5 v0 K+ d l

{ $ n2 U5 e$ [6 d9 v3 `: Dclrscr(); cprintf("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 . . ."); gotoxy(14, 4); getch();

clreol(); 7 N$ i# @4 e" {- @* H( lgetch();

return 0; } 2 Q( D8 C. x8 H5 ~ 8 G" h. e& I* V

函数名: clrscr , n) {( \1 r) p; j) ]功 能: 清除文本模式窗口 用 法: void clrscr(void); t+ D+ t% D; f6 q6 a( {5 w程序例:

#include

int main(void) { int i;

clrscr(); for (i = 0; i < 20; i++) # b% B% `3 y+ i) C9 ]$ F# ]" N- ncprintf("%d\r\n", i); ; W4 Y9 [# {9 Z) @8 |" }cprintf("\r\nPress any key to clear screen"); getch();

' u$ G0 G& s* [ _; f

clrscr(); " @2 u$ A3 V& K2 w' Hcprintf("The screen has been cleared!"); ) O0 Q) m' r1 Y2 `4 M n! Dgetch();

6 ]1 n# J, x& w- l0 {( B- b @

return 0; * O" o0 A7 l' A1 ?4 u} H' d* o4 H6 z6 b) Q7 M; ]8 \ 3 k( @- P# X6 A3 e6 j, f+ ~

函数名: coreleft / W+ M9 \, y4 R- @功 能: 返回未使用内存的大小 用 法: unsigned coreleft(void); ) R+ w, ^8 Z% n9 v- \. C0 Q程序例:

I6 L4 O8 K, f: M2 {/ m: n

#include 8 w9 [. g6 [* L1 j8 H$ @#include

int main(void) 0 i7 S8 A/ n9 |{ 4 w: ]) m& |7 k3 C0 t" Lprintf("The difference between the highest allocated block and\n"); printf("the top of the heap is: %lu bytes\n", (unsigned long) coreleft());

1 W. `0 C6 e6 ?3 R$ P

return 0; ; b+ B3 U# y/ ?}

' S: _/ s/ c3 J8 f, ]

函数名: cos ^8 h+ p# _2 A0 t功 能: 余弦函数 用 法: double cos(double x); 5 c, W" F# E; f: s0 o程序例:

# e0 G: I6 U; ^- ]: _; x) {0 D

#include & D; _9 x- V' v4 w. a+ s) k#include

5 V% U* w3 M z) p1 B; A) p

int main(void) { double result; * H+ S; R) q3 `6 f, m+ I8 t& v) @double x = 0.5;

$ C4 Z& l6 \+ C

result = cos(x); printf("The cosine of %lf is %lf\n", x, result); - J3 P: W0 a- \4 Q oreturn 0; } ( d; s# |( ^' T- _ f' T0 P# D4 `

- w3 M E. {# R" _, |) w9 i, T

函数名: cosh 功 能: 双曲余弦函数 1 ]1 \0 L( f3 B, ^) N7 _用 法: dluble cosh(double x); $ Y7 g6 y" M [/ x, C程序例:

#include 4 B3 [; a; ^( }7 p- @: \/ n. x#include

7 z! G% o, B- p

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

result = cosh(x); printf("The hyperboic cosine of %lf is %lf\n", x, result); return 0; } 0 Y. a5 C0 M: ]( }- r% j3 x

函数名: country 1 k7 _$ ?3 R- [( A9 Z) C( J功 能: 返回与国家有关的信息 * m; J/ ]; K% P2 b0 _8 m用 法: struct COUNTRY *country(int countrycode, struct country *country); " @+ }: n0 e0 G5 A" |程序例:

+ L+ v! p; ?: L9 U2 S

#include 8 G6 d/ y% Z5 h) P5 p' Q#include

# x# F0 s8 o# l) }

#define USA 0

+ q! B" E8 {4 x) j R

int main(void) { , @3 H8 M5 l; Z6 w! g7 Bstruct COUNTRY country_info;

country(USA, &country_info); 6 @$ p7 x/ J: h9 t c* i( D& s, I/ fprintf("The currency symbol for the USA is: %s\n", country_info.co_curr); / e; D1 S, O1 @3 P. J+ breturn 0; } ; w+ \$ E3 U! U @; m! c' t# X ' K6 D" x9 `+ b$ C, s; D& x( X/ m) ~ 6 J+ x5 s; t0 f: T/ X1 a

! S6 z7 c6 L# x) b

函数名: cprintf 3 W) ^( L7 E$ v功 能: 送格式化输出至屏幕 + K4 X4 V; t9 a/ R7 V. p+ z用 法: int cprintf(const char *format[, argument, ...]); 2 W! ]1 Y3 u: R$ S) D' T$ f6 s( N- j! p程序例:

1 O" T4 e: S9 X4 ]$ V5 D# T* x$ N

#include

5 I7 z/ t. `" y

int main(void) 2 Q F, }& a9 g5 ^{ /* clear the screen */ clrscr();

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

/* output some text in the window */ & k! m* v+ _5 l4 J) @- {# Mcprintf("Hello world\r\n");

/* wait for a key */ getch(); , X% x0 s: I* C% Hreturn 0; } % I* U9 l4 Y4 d. k0 D7 e& w

, E: |/ q/ z. P, D2 C

函数名: cputs 功 能: 写字符到屏幕 2 J: e r1 N: {0 _! c9 B9 k k用 法: void cputs(const char *string); : w5 a% t7 L6 h: R9 q程序例:

#include

& Y: X0 \5 ~& F- j& }: F& L

int main(void) , j5 X' k6 C1 R, o{ /* clear the screen */ 0 ]4 z; Q; q' h9 R& B' N5 Z$ Hclrscr();

! X4 Q+ z( F* q8 q, T7 G% v$ g

/* create a text window */ 7 m, c. D- K% Qwindow(10, 10, 80, 25);

; }# h) F1 y& k( q7 B) E, H

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

/* wait for a key */ 8 t L7 S* P% g, M' i& Ugetch(); return 0; } 2 M2 w( S% T E3 _ 8 _3 s, C6 ]* Z/ R! A2 H 2 u# ?) Q! g! v/ S+ L6 c2 a9 q( K

* H* |8 M9 t. b+ I

函数名: _creat creat / F; d! B5 G3 s/ h8 t( R功 能: 创建一个新文件或重写一个已存在的文件 " z* }% m8 K1 x1 `+ ^6 ]1 ?7 r用 法: int creat (const char *filename, int permiss); 程序例:

+ b7 E; j. _( x2 \! R

#include #include " t2 J0 ~: z2 |#include #include

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

( `0 t+ p' D8 `# F! d- o1 E: J' Q: m

/* change the default file mode from text to binary */ 5 R8 U1 u7 b- a% E/ w- I9 k_fmode = O_BINARY;

/* create a binary file for reading and writing */ 1 g' P! k) h" V. z% dhandle = creat("DUMMY.FIL", S_IREAD | S_IWRITE);

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

/* close the file */ ( }1 A- l& `$ e% Y9 \& `close(handle); return 0; . s( G9 C: B) X2 ?}

函数名: creatnew 功 能: 创建一个新文件 用 法: int creatnew(const char *filename, int attrib); 程序例:

2 I& D2 {! ]+ Z* R/ J1 ~- h- f

#include ) ?+ b1 S; v% [: B3 S#include 4 H" x$ T( w+ h O% x: E% h3 j#include , B7 o9 {) `/ f$ G#include #include

. o4 P' o) w' m7 q

int main(void) ) e( j' ~. F$ m7 u; \{ int handle; char buf[11] = "0123456789";

/* attempt to create a file that doesn't already exist */ & i& d2 k2 y* y4 O/ ~+ U4 m3 r1 khandle = creatnew("DUMMY.FIL", 0);

7 F6 M6 T" q: f# w$ T6 x% v

if (handle == -1) 7 g* l0 A3 R4 w) `! J3 ]printf("DUMMY.FIL already exists.\n"); else { printf("DUMMY.FIL successfully created.\n"); / V; U. q9 Q' \7 `write(handle, buf, strlen(buf)); : X5 @4 f0 w6 l% ^! Y7 tclose(handle); } return 0; - _8 ^( x) Q) d0 F: Z( H2 z( D} ; s- t' A1 h: Q% j) g% g8 S

函数名: creattemp 功 能: 创建一个新文件或重写一个已存在的文件 - w* ?9 m+ B+ h用 法: int creattemp(const char *filename, int attrib); 程序例:

0 h4 q& d( J3 E/ a$ ?

#include 4 g0 \; z+ ^0 k! ?. G6 a/ p4 i#include ) c! i& W: W8 P& s/ ]) {; t#include

/ \, \3 U3 B0 l) R6 I

int main(void) 7 d4 F, i+ d! w# R) W% p6 `' p2 e% M{ int handle; char pathname[128];

strcpy(pathname, "\\");

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

8 _& |1 q: _0 V4 `2 D% j

printf("%s was the unique file created.\n", pathname); ) y' f' {5 S2 N& Y& pclose(handle); return 0; 1 e/ J0 `' y3 Y7 {; \& |} 1 C0 [: O; z4 l* S$ t! A @" z 2 v. h2 K( @, i4 X% d4 f. v( F

' X2 X* g1 ]+ @8 {0 Y- y: N

函数名: cscanf 功 能: 从控制台执行格式化输入 ; d3 m2 a( G5 o O用 法: int cscanf(char *format[,argument, ...]); 程序例:

' B; o. y4 w7 K; q1 a

#include

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

1 @) W# k+ s6 l( _: `, K3 t

/* clear the screen */ 0 E( ]( K8 C4 r' F/ ?" t# [clrscr();

/* Prompt the user for input */ 0 t- T+ t9 V0 f: b) G2 Wcprintf("Enter a string with no spaces:");

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

T8 [' N* u, P( a

/* display what was read */ # i4 O( T) `& Q% N' X5 U3 \, ycprintf("\r\nThe string entered is: %s", string); return 0; 4 I7 Q* p5 C' t3 F; z& w} S5 E" D' P1 D% \1 B4 M

6 l' z. g" T; |7 M; E

函数名: ctime ( l; ^- w/ {8 u+ j/ |功 能: 把日期和时间转换为字符串 / t6 n `* V4 j/ |用 法: char *ctime(const time_t *time); 程序例:

#include 4 k) y9 I; n3 h" d6 u3 g9 v* v#include

int main(void) # d5 N# Q4 X: I3 k$ m, p" [{ time_t t;

time(&t); 9 d' n# Q% ]1 r9 g1 hprintf("Today's date and time: %s\n", ctime(&t)); 2 `0 g' l! \7 E @return 0; } & k3 T; X6 X: h3 P+ g . B3 Y) r- I" k* z: D; D! |9 P4 G6 _

+ u/ m9 u( V, s. D) \

函数名: ctrlbrk 功 能: 设置Ctrl-Break处理程序 用 法: void ctrlbrk(*fptr)(void); 8 g$ s" J. g! p8 d/ L; d( R$ ]6 W程序例:

#include 9 M4 s7 I3 B- O+ S3 g7 F$ ]#include

#define ABORT 0

' V4 F( t, U9 z5 h

int c_break(void) { - Z. V4 `* ?( Y4 E+ Tprintf("Control-Break pressed. Program aborting ...\n"); return (ABORT); 4 T- A3 X* \" U- r}

int main(void) ' M# Y+ f9 {. p& y% E{ ! l+ Q. }: J( T& B- hctrlbrk(c_break); + Q! `- w [1 [& k+ `8 U% Dfor(;;) $ W5 ~! K% c8 Y7 m6 E: h{ ' o4 ^) \9 i3 h# O6 D7 n9 xprintf("Looping... Press to quit:\n"); } return 0; 1 I0 J6 u, Z1 A}

hjl19890710hjl

特别感谢

gssdzc

还是感谢分享。。。

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

chenlk

有价值！

zjf

[em49]

谢谢啊