#ifndef PCRE2_CODE_UNIT_WIDTH
#define PCRE2_CODE_UNIT_WIDTH 8
#endif

#include <stdio.h>
#include <string.h>
#include <pcre2.h>

int main(int argc, char **argv)
{
    pcre2_code *re;
    PCRE2_SPTR pattern;     /* PCRE2_SPTR is a pointer to unsigned code units of */
    PCRE2_SPTR subject;     /* the appropriate width (in this case, 8 bits). */

    int errnum;
    int i, rc;

    PCRE2_SIZE erroffs;
    PCRE2_SIZE *ovector;
    PCRE2_SIZE subject_length;

    pcre2_match_data *match_data;

    if (argc != 3) {
        printf("Exactly two arguments required: a regex and a subject string\n");
        return 1;
    }

    pattern = (PCRE2_SPTR)argv[1];
    subject = (PCRE2_SPTR)argv[2];
    subject_length = (PCRE2_SIZE)strlen((char *)subject);

    re = pcre2_compile(pattern, PCRE2_ZERO_TERMINATED, PCRE2_UCP, &errnum, &erroffs, NULL);

    if (re == NULL) {
        PCRE2_UCHAR buffer[256];
        pcre2_get_error_message(errnum, buffer, sizeof(buffer));
        printf("PCRE2 compilation failed at offset %d: %s\n", (int)erroffs,
               buffer);
        return 1;
    }

    match_data = pcre2_match_data_create_from_pattern(re, NULL);

    rc = pcre2_match(re, subject, subject_length, 0, 0, match_data, NULL);

    if (rc < 0) {
        switch(rc) {
        case PCRE2_ERROR_NOMATCH:
            printf("No match\n");
            break;
        default:
            printf("Matching error %d\n", rc);
            break;
        }
        pcre2_match_data_free(match_data);   /* Release memory used for the match */
        pcre2_code_free(re);                 /*   data and the compiled pattern. */
        return 1;
    }

    ovector = pcre2_get_ovector_pointer(match_data);

    for (i = 0; i < rc; i++)
        printf("%2ld: %.*s\n", ovector[2*i], 
			     (int)(ovector[2*i+1] - ovector[2*i]),
			     subject + ovector[2*i]);

    pcre2_match_data_free(match_data);  /* Release the memory that was used */
    pcre2_code_free(re);                /* for the match data and the pattern. */

    return 0;
}
