C, segmentation fault

exvor · 09-10-2005, 06:56 AM

maybe something like this

Code:

 


// asumeing FILE is text 

   do {
    
     printf("%c",fgetc(text)); 
      
     } 
   while (fgetc(text) != 'EOF');

Goblin_C_Noob · 09-10-2005, 09:03 AM

nah thats fixed, WAY past that.

im now at the point were im trying to read in a string from the kb and send it to a function.

Code:

char*compare=(char*)malloc(sizeof(char*)*20);
scanf("%s",compare);
ReadCatalogue(myfile,*choice,compare);

//ReadCatalogue takes in:

void ReadCatalogue(FILE *myfile, int choose, char*compare)

this is were it starts laughing at me

.

why? And what can i do to fix it?

Goblin_C_Noob · 09-10-2005, 07:15 PM

ok, heres the deal:

Code:

myfile=fopen("getlin.txt","r+");
char*compare=(char*)malloc(sizeof(char*)*20);
int*choice=(int*)malloc(sizeof(int*)*2);
scanf("%d",choice);
printf("\nWhat would you like to search for?");
scanf("%s",compare);
printf("%s\n",compare);
ReadCatalogue(myfile,*choice,*compare);    /*Call to function, ReadCatalogue, (this is were it segments)*/



void ReadCatalogue(FILE *myfile, int choose, char**compare)     /*The called function, ReadCatalogue*/

is anyone able to suggest a reason for this?

i know it has something to do with my arguments when calling ReadCatalogue cause i get this warning when compiling

warning: passing arg 3 of `ReadCatalogue' makes pointer from integer without a cast.

this wasnt covered in the lecture notes and i havent a clue what it means.

Lux Perpetua · 09-11-2005, 05:50 AM

compare is a char *, so *compare is a char. ReadCatalogue is expecting a char **, not a char.

Goblin_C_Noob · 09-11-2005, 08:09 AM

hehe, you guys must be really getting tired of my noobishness.

Code:

char *Catalogue = malloc(sizeof(*Catalogue)*10);
Catalogue = "a";
printf("What file would you like to load? ");
scanf("%9s",Catalogue);
ReadCatalogue(myfile);

segments here

this is really starting to piss me off too, so im sorry for all those that read my code and start rocking in your chairs because of how bad it looks, but i dont do it on purpose.

i also get the same problem here:

Code:

char *Catalogue = malloc(sizeof(*Catalogue)*10);
Catalogue = "a";
myfile=fopen(Catalogue,"r+");
int*choice = malloc(sizeof(*choice)*2);
choice = 0;
scanf("%1d",choice);

Goblin_C_Noob · 09-11-2005, 09:48 AM

never mind, thanx guys i fixed it, but only with your expert help.

Goblin_C_Noob · 09-11-2005, 10:48 AM

hey, just me again:

new segfault and this one aint my fault

Code:

char *temp = malloc(sizeof(*temp)*10);
temp[0]='a';
scanf("%9s",temp);

thats it, it segfaults at scanf and i dont know why.

Zayar Win · 12-16-2007, 09:09 AM

Yeah, you fixed my problem!!! Thanks!!!