Thread: Need help.

Code:

while(!foef(binfile1) || !feof(binFile2))

Presumably you meant "feof", not "foef", but you're right about it not working.

Code:

          while((fgets(&itemM1, sizeof(INV_REC), binFile1) != NULL) ||
	   (fgets(&itemM2, sizeof(INV_REC), binFile2) != NULL))

You're saying "while this file still has some data or that file still has some data". In other words, both files have to reach EOF for the loop to exit. I think you probably want "&&" instead, because you assume that both files were read from in your loop.

Oh, of course. fgets() reads strings. Since you're already using fread() and fwrite() to write structures, all that remains is for you to check the return values of these functions.

fread(), for example, returns the number of items successfully written. Since you're writing one item at a time, something like this would work.

Code:

if(fread(&itemM2, sizeof(INV_REC), 1, binFile2) == 1) {
    /* success */
}
else {
    /* failure */
}

Notes: break; can be used to exit from a loop at any time, should you want it. Also, you can use sizeof() on a variable, which eliminates the possibility that you'll mess up the type.

Code:

fread(&itemM2, sizeof(itemM2), 1, binFile2);

Code:

if(fread(&itemM1, sizeof(itemM1), 1, binFile1) == 1);
     if(feof(binFile1))
     itemM1 = sentinel;

First: that red semicolon would mess you up.

Now, keep in mind what these functions do.

• feof(): checks for EOF without reading anything. Only useful directly after a function call that actually reads something.
• fread(): reads data from a binary file. Returns number of items successfully read.
• fgets(): reads a string from a text file.

You only need one of those functions: fread. feof() checks for EOF, but you know that anyway by looking at fread()'s return value. fgets() is for reading strings, which you don't want at all.

What I would do is this. Every time you call fread(), check its return value. If the return value isn't 1, you have reached the end of the file. How you handle that is up to you. You only need a loop if you want to keep reading from a file until you reach the end of the file; and if you did use a loop, you'd use it in conjunction with fread.

Code:

while(fread(...) == 1) {
    /* ... */
}

Does that answer your question? . . . .

And another thing: try indenting your code properly. It really helps. cpwiki.sf.net/Indentation

First, I'm going to indent your code (with "indent -kr") because I couldn't read it at all. Oh, and codeform it too.

Code:

void mergeBinFiles(FILE * binFile1, FILE * binFile2, FILE ** binOutFile)
{
//Local Declarations
    INV_REC itemM1;
    INV_REC itemM2;
    INV_REC sentinel = { 9999 };
    int mergeCnt = 0;
//int fp1;
//int fp2;

//Statements
    printf("\nBegin File Merge:\n");
    fread(&itemM1, sizeof(INV_REC), 1, binFile1);
    if (feof(binFile1))
	itemM1 = sentinel;
    fread(&itemM2, sizeof(INV_REC), 1, binFile2);
    if (feof(binFile2))
	itemM2 = sentinel;

    while ((fgets(&itemM1, sizeof(INV_REC), binFile1) != NULL) ||
	   (fgets(&itemM2, sizeof(INV_REC), binFile2) != NULL)) {
	if (strcmp(itemM1.partNo, itemM2.partNo) >= 0) {
	    fwrite(&itemM2, sizeof(INV_REC), 1, *binOutFile);
	    mergeCnt++;
	    fread(&itemM2, sizeof(INV_REC), 1, binFile2);
	    if (feof(binFile2))
		itemM2 = sentinel;
	}			//if                    
	else {
	    fwrite(&itemM1, sizeof(INV_REC), 1, *binOutFile);
	    mergeCnt++;
	    fread(&itemM1, sizeof(INV_REC), 1, binFile1);
	    if (feof(binFile1))
		itemM1 = sentinel;
	}			//else
    }				//while
    printf("\nFiles Merged. %d items merged.\n", mergeCnt);
    system("Pause");
    return;
}				//mergeBinFiles

See, there's lots of stuff going on there that I wasn't really aware of . . . .

First thing: you don't want to use fgets(). It reads strings. You're trying to merge two binary files, so fgets() has no place here.

Now, it looks like your loop doesn't actually have to read anything at all. fread() before and inside the loop takes care of the file reading.

Maybe what you want is this.

Code:

while(itemM1 != sentinel && itemM2 != sentinel)

You already detect EOF and set itemM1 and/or itemM2 to sentinel when one of the files reaches its end. All you have to do is continue until both of the files have ended.

Note: you can't use strcmp() on numbers. I'm guessing INV_REC::partNo is a number, because you initialize sentinel with 9999. Just use plain old

Code:

if (itemM1.partNo >= itemM2.partNo) {

Thank you again. If I should have any more questions do you mind if I ask?

Fire away. It's what we do best -- answer questions. Sorry I took so long to do a full examination of your code . . . .

Good luck with programming.

Mmm, that's good, I was a bit stumped.

Also look at this:

Code:

        if(!ioResult)
        if(!feof(binOutFile))
           {
           printf("\nError reading binOutFile.\n");
           system("Pause"), exit(501);
           }//if !feof

What you're saying is: "if no items were read from the file, then: if the end of the file has not been reached, then: print an error . . . ."

In other words, you shouldn't have a ! on that feof. Come to think of it, you can just use this:

Code:

        if(!ioResult)
           {
           printf("\nError reading binOutFile.\n");
           system("Pause"), exit(501);
           }//if !feof

[edit]

I want you to know how much I appreciate your help.

You're welcome. Thanks are appreciated. [/edit]

Code:

ioResult = fread(&stkList, sizeof(stkList), 1, binOutFile);

You're trying to read from an output file, judging from its name at least.