strcpy replaced by a better function

[Guest_imported]

Hello

as you know strcpy can be fatal, if dest is not as big as src. In this case an error can occur.

For this I did my own strcpy-function:

//Allocates memory for dest as much as needed
void scopy(char *dest, const char *src)
{
if ( (dest = (char*) malloc( (strlen(src) + 1) * sizeof(char) ) ) != NULL )
strcpy(dest, src);
else
{
fprintf(stderr,"Error while copying string\n",);
exit(1);
}
}

But this permanently causes errors. What's wrong?

Any help is greatly appreciated.

Thanks in advance.

BinLadenKiller

 

[shail]

hi blk,
what errors do u c?
how about this.. ?

void scopy(char **dest, const char *src)
{
if ( (*dest = (char*) malloc( (strlen(src) + 1) * sizeof(char) ) ) != NULL )
strcpy(*dest, src);
else
{
fprintf(stderr,"Error while copying string\n",);
exit(1);
}
}

in using..
char *mydest, char str[]="hello";
scopy(&mydest, str);
.. use ..
free(mydest); // this bcomes a essential and possible error source for ur application.. each ptr will need to b free'd
secondly u cannot copy char *const ptrs!!

hope that helps,
shail

 

[Guest_imported]

Hello shail,

yeah, ur absolutely right. Now I see the problem.

Thank you very much.

BinLadenKiller

 

[mageshbabu]

I think the error is in the comparision stmt:

(dest = (char*) malloc( (strlen(src) + 1) * sizeof(char) )


what u 're doing is checking the pointer's address of the two pointers,not the length.It seems so.


Magesh

 

[Jay1Roy]

Magesh,

The statement with pointers is perfect! The error was somewhere else... the addresses in the pointers played the trick!;-)

Chow!

J Roy