Thanks. I've replaced that code with the code below. If you see any fault in the new code, please reopen this bug.

#include <sys/types.h>
#include <sys/stat.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int
main(int argc, char *argv[])
{
    struct stat sb;
    char *buf;
    ssize_t nbytes, bufsiz;

    if (argc != 2) {
        fprintf(stderr, "Usage: %s <pathname>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    if (lstat(argv[1], &sb) == -1) {
        perror("lstat");
        exit(EXIT_FAILURE);
    }

    /* Add one to the link size, so that we can determine whether
       the buffer returned by readlink() was truncated. */

    bufsiz = sb.st_size + 1;

    /* Some magic symlinks under (for example) /proc and /sys
       report 'st_size' as zero. In that case, take PATH_MAX as
       a "good enough" estimate. */

    if (sb.st_size == 0)
        bufsiz = PATH_MAX;

    buf = malloc(bufsiz);
    if (buf == NULL) {
        perror("malloc");
        exit(EXIT_FAILURE);
    }

    nbytes = readlink(argv[1], buf, bufsiz);
    if (nbytes == -1) {
        perror("readlink");
        exit(EXIT_FAILURE);
    }

    printf("'%s' points to '%.*s'\n", argv[1], (int) nbytes, buf);

    /* If the return value was equal to the buffer size, then the
       the link target was larger than expected (perhaps because the
       target was changed between the call to lstat() and the call to
       readlink()). Warn the user that the returned target may have
       been truncated. */

    if (nbytes == bufsiz)
        printf("(Returned buffer may have been truncated)\n");

    free(buf);
    exit(EXIT_SUCCESS);
}