- Find Non Ascii Characters In Text File Notepad Yahoo Online
- Find Non Ascii Characters In Text File Notepad Yahoo Login
Wrote: hi friends,i've been having this confusion for about a year, i want to know theexact difference between text and binary files.As far as the C standard is concerned there are some things like notbeing able to get the exact file size with binary files, file positionmay be off with text files, there being a maximum line length for textfiles, and each line in a text file must be outputted with 'n'. Thisis a summary, check the standard for the real list. So basicallywriting a file in text mode then opening it in binary mode isn'tguaranteed to even give you anything meaningful or work at all (imaginean implementation that marks whether a file has a text or binaryattribute and a file is determined by both the filename and thisattribute).On many implementations, the above doesn't apply and all you have toworry about how the implementation stores the newline character. Sinceyou're on Windows, here is the convention for text files (treating thetext file as binary here):BOM(optional)line1 newline.lineN newline(optional)EOF(optional)the BOM is to handle unicode files, it can be one of:0xEF 0xBB 0xBF (UTF-8 BOM)0xFF 0xFE (UTF-16LE BOM)0xFE 0xFF (UTF-16BE BOM)If there is no BOM, then it's up to the software opening it to figureout the encoding of the file somehow.Newline is the 'r' 'n' sequence of characters.Lines are composed of characters. For UTF-16, these characters areeither 2-bytes or 4-bytes depending if they're surrogate pairs. ForUTF-8, characters are 1, 2, 3, or 4 bytes.
(and on top of all this, youhave to deal with an arbitrary number of combining characters). Youshould read up on unicode, UTF-8, and UTF-16 because this whole issueof characters and glyphs is confusing when somebody like me uses looselanguage like this. If it's not a Unicode file, it most likely usessome encoding set on the system. Generally white-people countries use1-byte per character and non-white-people countries use multiple bytesto encode characters.EOF is the ASCII ctrl+Z code (0x19). You won't find this except whenopening an ancient DOS file off a floppy or something.When opening a file in text-mode, most of this should be transparent toyou if your program and the C runtime were carefully designed. Theabove should pretty much be a concern for the C runtime implementors orprogrammers that want to handle all of this themselves.Here's some homework for you:On the C side, read 7.19, 7.24, and 7.25 in the C standard.
What's “Unicode encoding”?Unicode is a character set; there are lots of encodings between Unicode and bytes, many of them mapping only a subset of possible characters.When you want to use non-ASCII Unicode characters in a PHP script, the usual best choice of encoding is UTF-8, as it's an ASCII-superset encoding (ie. The lower 128 values of each byte always mean the standard ASCII characters) that can still represent any Unicode character. PHP, like many other byte-oriented tools, can only reliably work with ASCII-superset encodings.If by “Unicode encoding” you mean the thing that Notepad and other Windows tools call “Unicode”, that's quite a different proposition. This is a misleading name for what is correctly known as the UTF-16LE encoding. This encoding has a two-byte-per-code-unit width, which means eg that normal ASCII characters come out with zero bytes between them. It's not an ASCII-superset, so PHP and other byte-based tools can't do much with it directly.When saving scripts in Windows-based editors, look to save in UTF-8 (without BOM), and serve your pages with a UTF-8 Content-Type charset.
Find Non Ascii Characters In Text File Notepad Yahoo Online
Although it's the default in-memory representation for Windows, Java and JavaScript, UTF-16LE is of pretty much zero use for storing files or serving web pages. 'there are lots of encodings between Unicode and bytes, many of them mapping only a subset of possible characters' — that is completely false. Any valid Unicode encoding allows for all characters save alone those very few that Unicode designates as not valid for open interchange so you can use them as internal sentinels. UTF-8, UTF-16, and UTF-32 all encode all Unicode characters.
Find Non Ascii Characters In Text File Notepad Yahoo Login
If it cannot, it is not a Unicode encoding. ASCII encodes the first 128 code points; ISO-8859-1 the first 256. That by no means makes them Unicode encodings.–Apr 16 '11 at 0:12.