Re: confused about copying strings

Angus wrote:
The sample code below simulates receiving a protocol message with a tlv structure - type/length/data_value.

I am confused about copying the actual data to a temp string.

Since you know in advance that you have sufficient storage to store the copy, use strcpy.

int dtype = *mybytes++;
int dsize = *mybytes++;
size_t size = dsize;
char *data = malloc(size);
if(data != NULL)
{
if(strlen(mybytes) < size)
{
strcpy(data, mybytes);

printf("%s\n", data);

/* when finished with data... */
free(data);
}
else
{
something's wrong - your mybytes string length indicator is too low.
}
}
else
{
handle the out-of-memory error
}

data points to the /first/ character of the string - strcpy can't change data's value because we only passed its value, not the object itself. But strcpy can certainly copy the string to it.

<snip>

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
"Usenet is a strange place" - dmr 29 July 1999
Sig line vacant - apply within
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