Centering strings with printf()

printf by itself can't do the trick, but you could play with the "indirect" width, which specifies the width by reading it from an argument. Lets' try this (ok, not perfect)

void f(char *s)
{
        printf("---%*s%*s---\n",10+strlen(s)/2,s,10-strlen(s)/2,"");
}
int main(int argc, char **argv)
{
        f("uno");
        f("quattro");
        return 0;
}

There is no printf() format specifier to centre text.

You will need to write your own function or locate a library which provides the functionality that you're looking for.

@GiuseppeGuerrini's was helpful, by suggesting how to use print format specifiers and dividing the whitespace. Unfortunately, it can truncate text.

The following solves the problem of truncation (assuming the field specified is actually large enough to hold the text).

void centerText(char *text, int fieldWidth) {
    int padlen = (fieldWidth - strlen(text)) / 2;
    printf("%*s%s%*s\n", padLen, "", text, padlen, "");
}