ря

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

int main (int argc, char **argv)
{
    FILE *file_in, *file_out;
    char buff[300];
    int len;

    if (argc > 2)
    {
        if ((file_in = fopen(argv[1], "r")) != NULL)
            if ((file_out = fopen(argv[2], "w")) != NULL)
            {
                while (!feof(file_in))
                {
                    if (fgets(buff, 228, file_in))
                    {
                        len = strlen(buff);
                        if (buff[len - 2] == argv[3][0])
                        {
                            printf("%s", buff);
                            fprintf(file_out, "%s", buff);
                        }
                    }
                }
                fclose(file_in);
                fclose(file_out);
            }
            else
                puts("file could not be created!");
        else
            puts("file could not be opened!");
    }
    else
        puts("too few arguments!\nUsage:\nfindstr.exe [source file] [destination file] [last symbol in string]");

    system("pause");
    return 0;
}