.


:

:



,



( , )

:

































 

 

 

 
FAQ

.

⇐ 1234567 ⇒



 


 

 

 

 

' . ' () MS Windows. , -, , [1].

. ' , , . : Borland C++, Visual C++ .

MS Windows Visual C++ 6.0 ( ) , Windows, , , UNIX:

- ;

- , , ;

- , ' ;

- ;

- ;

- - .

, , . .

:

;

;

, , .

ѳ.

 

 


1.

, , .

 

. spawnl - spawnvpe ѳ , , .

 

.

 

"" , . , , . , . , , , , .

Visual C++ , , , . ( signal()) process.h 䳿:

1. (getpid).

2. (abort,exit,_exit).

3. (signal).

4. ( exec- spawn-, system-).

:

spawnl - .

spawnle - .

spawnlp - , PATH

spawnlpe - , PATH, .

spawnv -

spawnve - .

spawnvp - , PATH .

spawnvpe - , PATH , .

spawn-, main() .

main :

 

main(int argc, char *argv[],char *envp[]).

argc , main() . argv main . envp , (), .

argv[0] ' , , argc , . , , , . , . , , ѳ- :

 

:\>cprog Working program

 

cprog , argc argv :

 

arg=4

argv[0]="a:\cprog.exe"

argv[1]="Working"

argv[2]="C"

argv[3]="program"

argv[4]=""=NULL='\0'.

 

() , . :

 

" NAME = value "

 

NAME - ' , value . , value . NULL. :

 

PROMPT -

PATH - , O ,

COMSPEC - ' , .

 

:

 

envp[0]="PROMPT=$g$s"

envp[1]="path=a:\;c:\"

envp[2]="comspec=c:\command.com"

envp[3]=""=NULL'\0'.

 

Spawn - , . spawn ( exec -) . spawn - , ', , ' . spawn -.

 

#include <stdio.h>

int spawnl(modeflag,pathname,arg0,arg1...,argn,NULL);

int spawnle(modeflag,pathname,arg0,arg1...,argn, NULL,envp);

int spawnlp(modeflag,pathname,arg0,arg1...,argn,NULL);

int spawnlpe(modeflag,pathname,arg0,arg1...,argn, NULL,envp);

int spawnv(modeflag,pathname,argv);

int spawnve(modeflag,pathname,argv,envp);

int spawnvp(modeflag,pathname,argv);

int spawnvpe(modeflag,pathname,argv,envp);

int modeflag;

char *pathname;

char *arg0,*arg1...,*argn;

char *argv[];

char *envp[];

 

modeflag 䳿 . process.h modeflag :

P_WAIT - , , . ;

P_OVERLAY - ' , .

pathname , , . Pathname ( ), ( ) ' . pathname , "COM" . , "EXE" . pathname , . pathname , pathname . Spawnlp, spawnlpe, spawnvp spawnvpe , PATH, .

, , ( char). , , 128 . ('\\0') , , .

spawnl, spawnle, spawnlp, spawnlpe arg0, arg1... argn, , spawnv, spawnve, spawnvp spawnvpe argv.

̳ , arg0 argv[0], , . , ﳺ pathname.

spawnl, spawnle, spawnlp, spawnlpe , . argn NULL, .

spawnv, spawnvp, spawnve, spawnvpe , . argv. argv[0] ' pathname, argv[1] argv[n] , . argv[n+1] NULL , , .

spawnl, spawnlp, spawnv, spawnvp . spawnle spawnlpe, spawnve spawnvpe , envp . envp , , . envp NULL. envp NULL, .

1.1 spawn -. ' . : PATH , . . : .

1.1

PATH
spawnl PATH
spawnle PATH
spawnlp PATH
spawnlpe PATH
spawnv PATH
spawnve PATH
spawnvp PATH
spawnvpe PATH

 

Spawn - . 0, . exit . . spawn - -1, errno :

E2BIG - ;

EINVAL - modeflag;

ENOENT - ' ;

ENOEXEC - ;

ENOMEM - '.

³, , spawn -, , . , , setmode (). ', , -, .

 

1. . .

2. prog . Settings Project, Debug, Program Arguments. prog.exe.

3. , , spawn (8 ), prog.exe (8 ). , , , , . PATH. spawnl-spawnvpe 1 8 , , spawn. ' spawn- .

 

 

1. ?

2. Visual C++?

3. main?

4. ?

5. ?

6. spawn- PATH , ?

7. ?

8. spawn-?

9. ?

10. spawn- ?

2.

. .

 

. .

 

.

 

. . - . . . , , , . ', , , -, , , , , - . .

, . .

< 0 1 2 0 3 1 2 >. , , , - . - 0, < 1 2 0 3 1 2 > .

.

1. . 6 < 6 >.

2. , 2 < 6 7 3 7 1 >.

3. . 6.

4. . , 2 , < 2 6 7 3 7 1 >.

5. . , 2 , < 2 6 7 3 7 1 2 >.

6. . , < 6 7 3 7 1 2 >.

7. . ϳ < 6 7 3 7 1 >.

8. , . 7, < 6 3 7 1>.

9. () .

10. , , < 1 2 3 4 > < 9 8 7 5 >

< 1 2 3 4 9 8 7 5 >.

11. ﳿ .

4 6, 5 7, . - 5 6. , 4, 5, 6 7, .

. . , , :

struct list {struct name_age data;

struct list *next;};

data - ,

 

struct name_age {char *name; /* */

int age;}; /*³*/

next - .

. - struct list*;

, ' . next.

 

struct list{int val; /* */

struct list *next;};.

 

 

typedef struct list{int val;

struct list *next;} LIST;

 

LIST, LIST*.

#define END (LIST*)0.

 

 

, 1-11.

 

LIST* crtlst(int); /**/

int exist(LIST* h,int i); /* i h*/

int head(LIST* h); /* h*/

void uptoh(LIST** ph, int i);/* i (*ph)*/

void uptot(LIST* h,int i); /* i h*/

int delfromh(LIST** ph); /* (*ph)*/

int delfromt(LIST** ph); /* (*ph)*/

int del(LIST** ph, int i); /* i (*ph)*/

void print(LIST* h); /* h*/

LIST* concat(LIST* f,LIST* s);/*ᒺ f s */

LIST *dbl(LIST* s); /* */

 

LIST**. ³ , , .

head

 

int head(LIST* h);

{return h->val;}

 

, . ' . ѳ malloc free.

 

void* malloc(unsigned size)

 

' size . ' NULL. ', malloc,

 

void free(void *p)

 

- ', .

, '

 

LIST *j;

j=(LIST*)malloc(sizeof(LIST));

free(j).

.

 

LIST* crtlst(int l) /**/

{LIST* h=(LIST*)malloc(sizeof(LIST));

h->val=l; h->next=END;

return h;}

 

l. (END) next.

 

#define END (LIST*)0

void uptoh(LIST** h, int v) /* v (*h)*/

{LIST *oldh=*h;

*h=(LIST*)malloc(sizeof(LIST));

(*h)->val=v;

(*h)->next=oldh; }

 

, (*h).

 

int delfromt(LIST** h) /* (*h)*/

{ LIST *i,*j;

int v;

if((*h)->next==END)

{v=(*h)->val; free(*h); (*h)=END;return v;}

for(j=(*h),i=j->next;i->next;j=i,i=j->next);

v= i->val;free(i);

j->next=END;

return v;}

 

, . , .

 

void print(LIST* h) /**/

{LIST *i;

printf("\n ");

if(h==END) printf(" ");

for(i=h;i;i=i->next)

printf(" %d ",i->val); }

 

. , .

 

LIST*concat(LIST* f, LIST* s) /*ᒺ f s */

{LIST* i;

for(i=f;i->next;i=i->next);

i->next=s; return f;}

 

s f. ', f s. .

 

LIST *dbl(LIST* s) /* */

{LIST *p,*t,*i;

t=(LIST*)malloc(sizeof(LIST));

for(p=s,i=t;p->next;p=p->next)

{i->val=p->val;

i=i->next=(LIST*)malloc(sizeof(LIST));

}

i->next=END;

i->val=p->val;

return t;}

 

s t. ' ﳿ malloc. END.

 

.

 

1. . .

2. crtlst, delfromt, uptoh print.

3. , :

)

 

int exist(LIST* h, int i); /* i h*/.

 

, print. 1 0 .

) i

 

void uptot(LIST* h,int i); /* i h*/

, ' , , next . ', next 0 (END).

) .

 

int delfromh(LIST** ph); /* (*ph)*/.

 

. (*h) ' - .

) i

 

int del(LIST** ph, int i); /* i (*ph)*/

 

, delfromh, , delfromt. , , next. '. 1 -1 i.

3. :

 

#include <stdio.h>

typedef struct list{int val;

struct list *next;} LIST;

#define END (LIST*)0

LIST* crtlst(int);

int delfromh(LIST**);

void uptot(LIST*,int);

void uptoh(LIST**,int);

int delfromt(LIST**);

int del(LIST**,int);

int exist(LIST*,int);

void print(LIST*);

main()

{int i; LIST* h;

printf(" \n ? ");

scanf("%d",&i));

h=crtlst(i);

print(h);

while(1)

{printf(" \nֳ ? ");

scanf("%d",&i));

if(h==(LIST*)0){printf("\n \n");exit(1);}

print(h);

if (exist(h,i))

{printf(" \n %d \n",i);

printf(" \n %d (/n)?",i);

if(getche()=='y')

{del(&h,i);

if(h==END){printf("\n \n");exit(1);}

print(h); }

}

printf(" \n %d (/n)? ",i);

if(getche()=='y') {uptot(h,i);print(h);}

printf(" \n %d (/n)h? ",i);

if(getche()=='y') {uptoh(&h,i); print(h);}

printf(" \n (/n)?");

if(getche()=='y')

if(h==END){printf("\n \n");exit(1);}

else

{printf(" \n %d\n"

delfromh(&h));

print(h); }

printf(" \n (/n)?");

if(getche()=='y')

if(h==END) {printf("\n \n");exit(1);}

else

{printf(" \n %d\n"

delfromt(&h));

print(h);

}}}

 

 

1. ? .

2. ?

3. 11 . ³ .

4. ? ' ?

5. LIST**?

6. ? .

7. ' ? .

8. ѳ?

9. delfromt ?

3.

.

 

. , ' .

ѳ . 3 -:

- - ;

- - ;

- - .

(). - () , .

-. - , , , .

, , , . . , .

. ֳ stdio.h. EOF ( ) NULL ( ), FILE, . .

, . ' FILE, . ³ fopen. FILE, . :

 

FILE *fopen(char *pathname,char *type),

 

pathname - ' , , type - , :

"r" - ( );

"w" - , , ;

"a" - (); , ;

"r+" - ( );

"w+" - , ;

"a+" - ; , .

"w" "w+", .

(, , ). :

"t" - ( _ _ (CRLF) (LF), LF CR-LF; Ctrl-Z );

"b" - ( Ctrl-Z ).

, "rb" . "t".

fopen NULL.

, ѳ . :

stdin - ( , );

stdout ( , );

stderr - ( , );

stdprn - ( , ).

"abc.def" :

 

#include <stdio.h>

main()

{

FILE *stream;

if ((stream = fopen("abc.def","r")) == NULL) {

printf (" abc.def\n");

exit(1); /* 1*/}

}

, . , , , , .

 

int fclose(FILE *stream),

 

stream - , .

0 EOF .

, ' , , FILE .

 

#include <stdio.h>

main()

{ FILE *stream;

stream = fopen("abc.def","r");

if(EOF==fclose(stream))

printf(" abc.def.\n");

}

 

, - . . , , 1 , . , . . , ' ( ), .

fget fput.

int fgetc(FILE *stream) stream, , . , EOF. feof ferror.

 

# include <stdio.h>

main()

{FILE *stream;

char buffer[81];

int i, ch;

/* stream */

for (i = 0; i < 80 && ((ch = fgetc(stream)!= EOF) && (ch!= '\n'); i++)

buffer[i]= ch;

buffer[i]= '\0'; }

 

int fputc(int , FILE *stream) stream. EOF, . , feof ferror.

.

#include <stdio.h>

main()

{ FILE *stream;

char buffer[81];

int i, ch;

/* buffer stream*/

for (i = 0; i < 81 && ((ch = fputc(buffer[i], stream))! = EOF); i++);

}

fseek, - .

 

int fseek (FILE *stream, long offset, int origin).

 

, ' stream, , offset , origin. origin , stdio.h:

SEEK_SET - ;

SEEK_CUR - ;

SEEK_END - .

.

, ( a+, r+ w+) , . "a" "a+" , . , fseek rewind , . , .

, - . . . . 0.

.

 

#include <stdio.h>

main()

{FILE *stream; int result;

stream = fopen("data","r");

...

/* */

result = fseek(stream,0L,SEEK_SET);

}

- stream,

 

long ftell(FILE *stream),

 

-1L .

.

#include <stdio.h>

main()

{ FILE *stream;

long sition;

stream = fopen("data","rb");

...

sition = ftell(stream); }

 

ѳ , , . .

 

void rror (char string),

 

stderr. string, , , . errno, . sys_errlist, . error , errno, sys-errlist. rror , . errno .

.

,,,

{ FILE *p;

if(NULL==(p=fopen("file.dat","r")))

rror(" FILE.DAT"); }

 

FILE.DAT , :

FILE.DAT: No such file or directory.

, , FILE . ferror feof. void clearerr (FILE *stream), stream.

ferror

int ferror(FILE *stream)

, stream .

.

#include <stdio.h>

main()

{int i;

i=fputc ('*', stdin);

if (ferror(stdin)) {

rror(" ");

clearerr();}

}

stdin , : : Error 0.

, ' stream, int feof(stream). . , clearerr. fseek .

.

 

#include <stdio.h>

main()

{char st[100];

FILE *stream;

/*

, */

while (! feof (stream))

{

(fscanf(stream,"%s",st))

/* */}

 

ferror feof clearerr.

.

 

#include <stdio.h>

#include <stdlib.h>

main()

{FILE *stream;

int c;

/* : . */

if ((c=getc(stream)) == EOF) {

if (ferror(stream){

rror(" \n");

clearerr(stream);}

}

 

int cess(char *pathname, int mode),

 

: pathname mode. mode :

06 - ;

04 - ;

02 ;

00 - .

0, -1, . errno :

EACCES - ;

ENOENT - ..

.

 

#include<io.h>

main()

{ FILE *fn;

/* */

if ((cess("data",2))== -1) {

rror(" ");

exit(1); }

else

fn = fopen("data", "a");}

 

.

 

1. .

2.

 

FILE *rndfopen(char* path),

 

path . - . , , ( , ). , . FILE, , NULL . fopen cess.

3. rndfopen, , . ѳ.

. , " l" :

 

if(fseek(p,l, SEEK_SET))

rror("\n H !");

 

/* */

 

#include <stdio.h>

FILE *rndfopen(char*); /* */

char s[10], n[15];

main()

{long l, ll; int ,ii;

FILE *p;

printf("\n ?");

gets(n); /* */

if(NULL==(p=rndfopen(n))) /* */

{rror("\n .");

exit(1);} /* 1 */

while(1)

{ printf("\n?");

gets(s); /* - */

l=atol(s); -

l*/

< l.>

< ll.>

< ii.>

printf("\n %ld %c (%d).",ll,ii,ii);

printf("\n (/n)?");

if(getche()=='y')

{printf("\n ?");

c=getche(); /* . */

< l. >

< c ,>

printf("\n (/n)?");

if(getche()=='n')break;

}

< .>

}

FILE *rndfopen(char *n)

{ <ҳ .> }

 

4. ϳ :

) ra.dat .

' ? ra.dat

? 0

0 (-1)

(/n)? n

(/n)?

? 3

3 (-1)

(/n)?

? 4

(/n)

? 3

3 4 (52)

(/n)? n

(/n)

? 0

0 ²__0

(/n)?

? 1

(/n)

? 0

0 1 (49)

(/n)? n

(/n) n

 

ra.dat 4- :

'1' ²__1 ²__2 '4'

 

) . ra.dat. .

' ? ra.dat

? 0

0 1 (49)

(/n)? n

(/n)?

? 3

3 4 (52)

(/n)?

? 0

(/n)

? 5

5 (-1)

(/n)?

? 6

(/n)

? 4

4 ²__4

(/n)? n

(/n)

? 1

1 ²__1

(/n)?

? 2

(/n) n

 

ram.dat 6- :

'1' '2' ²__2 '0' ²__4 '6'.

 

 

1. -? ?

2. ?

5. , ?

6. ?

7. fopen?

8. ?

9. / ?

10. ?

11. ?

12. fgetc fputc ?

13. ?

15. ѳ- ?

17. ?

18. cess?

19. ra.dat ' ?


4.

⇐ 1234567 ⇒


:

: 2016-09-06; !; : 459 |

:

:

- - , .
==> ...

1459 - | 1464 -


© 2015-2024 lektsii.org - -

: 0.51 .