Thread: Problem making save function?

Hello everyone. I am a little stuck on my project that I am working on. I am almost done, but this save file is the problem. I have to give the user an option to save what their results of the program to the save file, which is what I am trying to do. It's just not coming out? Here is my code (which is only of the save method. In my program, the prototype and call from the main function is also there):

Code:

void save_file()
{
        char filename;
        char option[5];

        printf("Would you like to save a file of this data?");
        printf("Enter Yes or No: ");
        scanf("%c", option);

        if (option == Yes)
        {
                FILE *outfile = fopen(filename, "w");
                if(outfile == NULL)
                {
                        printf( "The File was not successfully open.\n ");
                        return -1;
                }

                fclose(outfile);
        }

        else
        {
                printf("No save file will be written\n");
        }
}

These are the errors I am getting:

Code:

ProjectTest2.c: In function âsave_fileâ:
ProjectTest2.c:87: error: âYesâ undeclared (first use in this function)
ProjectTest2.c:87: error: (Each undeclared identifier is reported only once
ProjectTest2.c:87: error: for each function it appears in.)
ProjectTest2.c:89: warning: passing argument 1 of âfopenâ makes pointer from integer without a cast
/usr/include/stdio.h:271: note: expected âconst char * __restrict__â but argument is of type âcharâ
ProjectTest2.c:93: warning: âreturnâ with a value, in function returning void

I have never had to write a file before, only had to open/read. So, I hope I am even doing this correctly? I am also unsure of my use of a void (the compiler sure doesn't seem happy about it), but I am unsure of what else to use? Is it even appropriate to be doing a save in a function (the only reason I did it was because my instructor wants the maximum use of functions)? Any guidance at all would be awesome!

Thank you!

Ugh, thanks. It's been a few weeks since we've done this, and I thought I was remembering correctly. I'll go back and review my old programs/notes, and will be back if I have more issues. Thanks!

You need to either hard code the filename or pass it into the function...
Also you need to return a success/fail result from this operation so that your other code can govern itself accordingly.
Also a couple of your variable types are a bit wonky...

Something like this...

Code:

int save_file(char *filename)
{
        char option;
        FILE *outfile;

        printf("Would you like to save a file of this data?  (Y/N) :");
        scanf("%c", option);                 // gets 1 character

        if (option != 'Y' && option != 'y')
          return 0;                              // not saved

        //open the file
       outfile = fopen(filename, "w");
       if (outfile == NULL)
         return -1;                            // file error     

       // write file data here

       fclose(outfile);
       return 1;                                // success
}

As a general hint... once you get something working... always spend a couple of minutes and see if there isn't a simpler way to accomplish the same goals.