sort-by-lines.c

#define _GNU_SOURCE
#include <stdio.h>

#include "src/list/extd-ccdll.h"

int main(int argc, char **argv)
{
    int argi;

    if ((argc != 3) ||
       ((argi = atoi(argv[2])) < 0))
        exit(EXIT_FAILURE);

    FILE *fptr;
    char *name = argv[1];

    if (!(fptr = fopen(name, "rt")))
        fprintf(stderr, "argv[1]: no such file\n");
    else
    {
        char   *line;
        ssize_t byte;
        size_t  zero = 0;

        ccdll(char*) list;
        ccdll_init(list);

        while ((line = NULL,
                byte = getline(&line, &zero, fptr)) != -1)
            ccdll_push_back(list, line);

        free  (line);
        fclose(fptr);

        #define SCMP_CCDLL_PREFETCH(a, b) \
            (strncmp(SREF_NEXT(a), SREF_NEXT(b), argi) <= 0)
        ccdll_sort_prefetch_extd(list, SCMP_CCDLL_PREFETCH);

        CCDLL_INCR_EXTD(line, list, free(*line))
            printf("%s", *line);
        ccdll_free(list);
    }

    return 0;
}