Is this me or Windows?

I have been trying to read all of the directories and files within a specified directory. This directory only contains subdirectories. They have names of F00 all the way to F49. I kept getting an error when it got to F12 so I decided to check it out. When I decided to printf all of the f.cFileNames's to the console, F12 contained incorrect characters. Here is the output from the command line:

Code:

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C:\Ben\F00\* - 12
C:\Ben\F01\* - 12
C:\Ben\F02\* - 12
C:\Ben\F03\* - 12
C:\Ben\F04\* - 12
C:\Ben\F05\* - 12
C:\Ben\F06\* - 12
C:\Ben\F07\* - 12
C:\Ben\F08\* - 12
C:\Ben\F09\* - 12
C:\Ben\F10\* - 12
C:\Ben\F11\* - 12
C:\Ben\↑{▼\* - 12
C:\Ben\F13\* - 12
C:\Ben\F14\* - 12
C:\Ben\F15\* - 12
C:\Ben\F16\* - 12
C:\Ben\F17\* - 12
C:\Ben\F18\* - 12
C:\Ben\F19\* - 12
C:\Ben\F20\* - 12
C:\Ben\F21\* - 12
C:\Ben\F22\* - 12
C:\Ben\F23\* - 12
C:\Ben\F24\* - 12
C:\Ben\F25\* - 12
C:\Ben\F26\* - 12
C:\Ben\F27\* - 12
C:\Ben\F28\* - 12
C:\Ben\F29\* - 12
C:\Ben\F30\* - 12
C:\Ben\F31\* - 12
C:\Ben\F32\* - 12
C:\Ben\F33\* - 12
C:\Ben\F34\* - 12
C:\Ben\F35\* - 12
C:\Ben\F36\* - 12
C:\Ben\F37\* - 12
C:\Ben\F38\* - 12
C:\Ben\F39\* - 12
C:\Ben\F40\* - 12
C:\Ben\F41\* - 12
C:\Ben\F42\* - 12
C:\Ben\F43\* - 12
C:\Ben\F44\* - 12
C:\Ben\F45\* - 12
C:\Ben\F46\* - 12
C:\Ben\F47\* - 12
C:\Ben\F48\* - 12
C:\Ben\F49\* - 12

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Here is the code used to do it:

Code:

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                                if (strncmp(f.cFileName, "..", 2) > 0)
                                {
                                        j++;
                                        directories[j] = (char *)calloc((strlen(base) + strlen(f.cFileName) - 1), sizeof(char));
                                        strncat(directories[j], base, strlen(base) - 1);
                                        strcat(directories[j], f.cFileName);
                                        strcat(directories[j], "\\*");

                                        printf("%s - %d\n", directories[j], strlen(directories[j]));
                                }

---

So, what the hell?! I checked all of the settings of F12 against all of the other folders and they were identical.

The space you allocate isn't long enough.
No account for the \\* and the trailing \0

Even so, that wouldn't have anything to do with the part of the string that is being affected, and why it is so consistent to occur on a single directory and no other.

Quote:

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Originally Posted by carrotcake1029

Even so, that wouldn't have anything to do with the part of the string that is being affected, and why it is so consistent to occur on a single directory and no other.

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Since you are "relying on undefined behaviour", there is nothing you can say about what is expected and what is not - overwriting the end of a buffer can cause a whole load of different things.

--
Mats

Ok, well I fixed it and the error still occurs.

Quote:

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Originally Posted by carrotcake1029

Ok, well I fixed it and the error still occurs.

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Show the fixed code, and perhaps you also should show the code that calls FindFirstFile/FindNextFile?

--
Mats

Code:

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                                if (strncmp(f.cFileName, "..", 2) > 0)
                                {
                                        j++;
                                        directories[j] = (char *)calloc((strlen(base) + strlen(f.cFileName) + 2), sizeof(char));
                                        strncat(directories[j], base, strlen(base) - 1);
                                        strcat(directories[j], f.cFileName);
                                        strcat(directories[j], "\\*");

                                        printf("%s - %d\n", directories[j], strlen(directories[j]));
                                }

---

Keep in mind on my strncat i copy 1 less byte, so I need to add just 2 iirc.

Here is where I call FindFirstFile

Code:

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        char *base = "C:\\Ben\\*";

        h = FindFirstFile(base, &f);

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Then it runs through a series of loops and such.

Code:

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        while (h != INVALID_HANDLE_VALUE)
        {
                while (FindNextFile(h, &f))

---

Try printing out f.cFileName each iteration and see if that's messed up.
Also, I'm assuming you ran DIR /X to see if the directory name itself is corrupted?

How about stepping through the code in a debugger and watching what happens? It's a great way to learn...

How is directories declared?

char **directories[10];
perhaps?

In which case, you need to add
&& j < 10
to whatever loop is running through all the directory entries.



> strncmp(f.cFileName, "..", 2) > 0
Use != 0
Directory names beginning with say space (which is legal) would not be caught by your code.