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# Example: rewind

This example creates a log file and writes the following to it:

- the string "Vuser"

- the integer "Vuser ID"

the time, as returned by the time function.

To read these values back again, the file cursor is moved to the beginning of the file, using rewind.

    #include <time.h>
    #include <stdio.h>
            #ifdef unix
                char *filename = "/tmp/logfile.txt";
            #else
                char *filename = "c:\\logfile.txt";
            #endif

        FILE* file, thetime;
        int id, id2;
        time_t t;
        char s[32];

        // Create a new file

        if ((file = fopen(filename, "w+" )) == NULL) {
            lr_output_message ("Unable to create %s", filename);
            return -1;
        }

        // Write the Vuser ID and time

        lr_whoami (&id, NULL, NULL);
        fprintf(file, "Vuser %d %ld", id, time(&t));

        // Now read what we've just written. Rewind to start of file

        rewind(file);
        fscanf(file, "%s", &s);
        fscanf(file, "%d", &id2);
        fscanf(file, "%ld", &thetime);
        lr_output_message ("%s %d %ld", s, id2, thetime);
        fclose(file);

    Example: Output:
    Vuser -1 1020675497

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