Re^4: create clone script for utf8 encoding

it might be important to note that there are certain sequences of bytes that are not valid UTF-8 (see e.g. UTF-8), which means that in some cases, it's possible to differentiate between random bytes and valid UTF-8 text.

I see.

Also, just to nitpick a little, it's not the OS guessing the file's encoding, it's the file tool.

Thank you for the delousifying reference at file. I pulled out what I thought was relevant. I've "known" this before, but if you get behind on reading, things change:

file tests each argument in an attempt to classify it. There are three sets of tests, performed in this order: filesystem tests, magic tests, and language tests. The first test that succeeds causes the file type to be printed.

The filesystem tests are based on examining the return from a stat(2) system call. The program checks to see if the file is empty, or if it's some sort of special file. Any known file types appropriate to the sys- tem you are running on (sockets, symbolic links, or named pipes (FIFOs) on those systems that implement them) are intuited if they are defined in the system header file <sys/stat.h>.

If a file does not match any of the entries in the magic file, it is examined to see if it seems to be a text file. ASCII, ISO-8859-x, non- ISO 8-bit extended-ASCII character sets (such as those used on Macintosh and IBM PC systems), UTF-8-encoded Unicode, UTF-16-encoded Unicode, and EBCDIC character sets can be distinguished by the different ranges and sequences of bytes that constitute printable text in each set. If a file passes any of these tests, its character set is reported. ASCII, ISO-8859-x, UTF-8, and extended-ASCII files are identified as `text' because they will be mostly readable on nearly any terminal; UTF-16 and EBCDIC are only `character data' because, while they contain text, it is text that will require translation before it can be read. In addition, file will attempt to determine other characteristics of text-type files. If the lines of a file are terminated by CR, CRLF, or NEL, instead of the Unix-standard LF, this will be reported. Files that contain embedded escape sequences or overstriking will also be identified.

Once file has determined the character set used in a text-type file, it will attempt to determine in what language the file is written. The lan- guage tests look for particular strings (cf. <names.h> ) that can appear anywhere in the first few blocks of a file. For example, the keyword .br indicates that the file is most likely a troff(1) input file, just as the keyword struct indicates a C program. These tests are less reliable than the previous two groups, so they are performed last. The language test routines also test for some miscellany (such as tar(1) archives).

You may have noticed that when using pre tags, you have to escape square brackets

I do now. Life is like a box of chocolates with pre tags for this particular forrest gump. The engine that parses the xml is gonna look at [ ] and create a hyperlink, isn't it? I think I'm gonna go back to code tags, even when content has cyrillic. Others can make a clean download without having to copy and paste off the screen.

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