Ficheiro de LOG

// Apple Xcode


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

#define BUFFER_SIZE 256

char *func_date(void)
{
    // date / time
    time_t the_raw_time;
    struct tm *the_time_info;

    // time: returns the value of time in seconds since the Epoch
    time(&the_raw_time);
    the_time_info = localtime(&the_raw_time);

    // format date / time
    static char the_buffer[BUFFER_SIZE];

    the_time_info = localtime (&the_raw_time);
    strftime(the_buffer, BUFFER_SIZE, "%Y-%m-%d: ", the_time_info);

    return the_buffer;
}


int main (int argc, const char * argv[])
{
    // ficheiro de log
    FILE *the_file;
    size_t the_count;

    // w+ create the file if it does not exist
    the_file = fopen("/Users/.../Desktop/log", "r+");

    if (the_file == NULL)
    {
        perror("erro na abertura do ficheiro");
        return EXIT_FAILURE;
    }

    // file size, put pointer at the eof
    fseek(the_file, 0, SEEK_END);
    long the_file_size = ftell(the_file);
    printf("ficheiro: %ld bytes\n", the_file_size);

    // strings
    char *the_test = func_date();
    char *the_string = "nova entrada.\n";

    // concatenate strings
    strcat(the_test, the_string);

    // output
    the_count = fwrite(the_test, 1, strlen(the_test), the_file);
    printf("escritos: %zu bytes. fclose(fp) %s.\n", the_count, fclose(the_file) == 0 ? "com sucesso" : "falhou");

    return 0;
}