Revisions to Need HELP! with server.c pset6 done 4 functions but can't find couse of problem

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edited Apr 13, 2017 at 12:50

1

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

added 8 characters in body

Source Link

edited Nov 7, 2016 at 11:23

Yuri Laguardia

2.6k
1
10
17

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable resultresult point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. Resultresult will now point to NULLNULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphplinkphp. See the problem there?

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. Result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

complementing answer

Source Link

edited Nov 7, 2016 at 11:00

Yuri Laguardia

2.6k
1
10
17

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. Result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

I can tell you one problem right away. This part won't work with pipe streams like php files:

//get the length of file in bytes
    fseek(file, 0, SEEK_END);
    byte_length = ftell(file);
    fseek(file, 0, SEEK_SET);

To get the load() function working correctly 100% of the time, one usually needs to read from the stream progressively and use realloc() when needed.

DinoCoderSaurus gave some advice about it here: pset6 (webserver) - hello.php not loading properly

EDIT to tackle index.php problem:

Look what's happening here:

result = (access(linkphp, F_OK) != -1) ? linkphp : NULL;
if (result != linkphp)
    free(linkphp);

result = (access(linkhtml, F_OK) != -1) ? linkhtml : NULL;
if (result != linkhtml)
    free(linkhtml);

return result;

Now suppose there is a file called index.php inside the directory. That first part of the code will make the variable result point to linkphp, but you don't return it, so the computer proceeds to analyze the rest of the code.

What comes next? Well, it checks for the existence of index.html... and let's suppose it doesn't exist. Result will now point to NULL.

At the end of the function, NULL will be returned, even though the correct answer would be to return linkphp. See the problem there?

Source Link

created Nov 6, 2016 at 15:00

Yuri Laguardia

2.6k
1
10
17

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