问题
I'm currently working with a PLC that supports ANSI C, but uses its own flavour of the GNU compiler, which doesn't compile any variadic functions and things like itoa. So using sprintf & co. isn't an option for converting integers to strings. Can anyone guide me to a site where a robust, sprintf- free implementation of itoa is listed or post a suitable algorithm here? Thanks in advance.
回答1:
This is from K&R:
void itoa(int n, char s[])
{
int i, sign;
if ((sign = n) < 0) /* record sign */
n = -n; /* make n positive */
i = 0;
do { /* generate digits in reverse order */
s[i++] = n % 10 + '0'; /* get next digit */
} while ((n /= 10) > 0); /* delete it */
if (sign < 0)
s[i++] = '-';
s[i] = '\0';
reverse(s);
}
reverse()
just reverses a string.
回答2:
Just for the sake of completeness and as a reference for others that may stumble upon the subject, I added this link to a recursive implementation of itoa itoa recursively which I like because of its simple beauty, but can't use for my target system.
来源:https://stackoverflow.com/questions/2138209/ansi-c-integer-to-string-without-variadic-functions