{"id":12,"date":"2005-08-17T20:11:47","date_gmt":"2005-08-17T14:41:47","guid":{"rendered":"http:\/\/jrtwine.com\/blog\/?p=12"},"modified":"2006-01-19T11:37:46","modified_gmt":"2006-01-19T15:37:46","slug":"null-nul","status":"publish","type":"post","link":"https:\/\/jrtwine.com\/blog\/null-nul\/","title":{"rendered":"NULL != NUL"},"content":{"rendered":"

I continue to find it rather amusing that even (so-called) experienced<\/em> developers will use fundamentally different concepts interchangeably, even after doing this for so long.
\n
\nFor example, I have seen documentation by developers that mention nul<\/strong><\/code> values in a database table, or worse yet, NULL<\/strong><\/code>-terminated strings, and NUL<\/strong><\/code> pointers.
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\nNow, some that simply miss the point<\/i> will be saying something like: “In C++, NULL<\/strong><\/code> is zero, and the NUL<\/strong><\/code> ASCII code has a value of zero, so they are the same thing<\/u>!”
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\nWrong.<\/b>
\n  The values<\/i> of the two identifiers may be the same, but not their meanings, and thus, it is inappropriate<\/b> to use them interchangeably.  Here is an example.  In the VC++ environment, the following identifiers are present:<\/p>\n

    NULL = 0\r\n    COLOR_SCROLLBAR = 0\r\n    MB_DEFBUTTON1 = 0\r\n    TRUE = 1\r\n    MB_OKCANCEL = 1\r\n    IDOK = 1\r\n    COLOR_BACKGROUND = 1<\/strong><\/pre>\n
But just because some of them have the same value <\/i>does not mean that it is correct to do something like this:<\/p>\n
    int iRet = COLOR_SCROLLBAR<\/b>                                 \/\/ Initialize iRet To What<\/strong><\/i> Value?\r\n\r\n    iRet = ::MessageBox( \r\n        \"Please press [OK] to continue or [Cancel] to cancel the delete operation.\", \r\n        \"Please Confirm Delete\", COLOR_BACKGROUND | NULL<\/b> );    \/\/ What<\/strong><\/i> Kind Of MessageBox?\r\n    if( iRet == TRUE<\/b> )                                         \/\/ What<\/strong><\/i> Button Are We Looking For?\r\n    {\r\n        \/\/ Do Delete Operation\r\n    }<\/pre>\n
According to the if the identifiers have the same value they mean the same thing<\/strong><\/i> argument, the code above is perfectly fine.  Of course, as demonstrated above, that is a bullshit argument.  After all, what would you think if you saw code written like that?  It would likely end up on The Daily WTF<\/a>.
<\/p>\n","protected":false},"excerpt":{"rendered":"
I continue to find it rather amusing that even (so-called) experienced developers will use fundamentally different concepts interchangeably, even after doing this for so long. For example, I have seen documentation by developers that mention nul values in a database table, or worse yet, NULL-terminated strings, and NUL pointers. Now, some that simply miss the […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-12","post","type-post","status-publish","format-standard","hentry","category-developing"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t