Inline::C not behaving as expected

[Ovid]

I'm playing around with Inline and I'm not getting the results that I expect. This snippet attempts to extract the date from a string and return it, but it's appending an 'x' to the end of the string. Any ideas why?

#!/usr/bin/perl -w
use strict;
use Inline C =><<'END_OF_C_CODE';
#include <string.h>
void get_date( char* str )
{
        /* much thanks to wog and talexb for suggestions */
        char date[9];    /* the date to return */
        int  index  = 0; /* index of character in string */

        Inline_Stack_Vars;
        Inline_Stack_Reset;
        while ( str[index++] != '|' );
        strncpy( date, &str[index], 8);
        Inline_Stack_Push(newSVpvf(date));
        Inline_Stack_Done;
}
END_OF_C_CODE

print get_date("adb|20011225|asdf");

This prints "20011225x". Any ideas why?

Cheers,
Ovid

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[wog]

Though you are using strncpy(), your string is not null-terminated. (update: to quote from the docs for strncpy on my machine "if there is no null byte among the first n bytes of src, the result will not be null-terminated.") To fix this probably you can do one of the following:

• Add a date[8] = '\0'; line.
• Use newSVpvn(date,8) to create a string of a specific length.

I would note that your current use of newSVpvf() should be replaced with newSVpv(date,0) or similar, to prevent odd behavior and/or major security flaws from popping up if your data contains %s. (Or, at least, to prevent you from getting in to the habit of coding that way for when it would matter.)