This page is part of the web mail archives of SRFI 75 from before July 7th, 2015. The new archives for SRFI 75 contain all messages, not just those from before July 7th, 2015.
On 23-Apr-06, at 4:54 AM, Jonathan S. Shapiro wrote:
...3. There is an issue with newline processing in input and output (whichprobably is the subject of a different SRFI). Platforms do not agree about newline conventions in text files. A regrettable consequence isthat character streams require specification at open time as to whetherthey are being opened for binary or text processing. One regrettable consequence of this is that the R5RS specification for open-output-file and open-input-file is inadequate. A second argument needs to be added to specify newline processing conventions. Note thatthis also became an issue for UNIX STDIO, and that acceptance of "t" and"b" in the file mode argument to fopen() is now mandated by the C standard. This is also an issue for string ports. In general, any operation that opens a port must specify the desired processing for newlines. ...9. Once you have a variable-length character representation, it becomesnecessary to incorporate separate means for reading bytes from input streams. For example this is needed if the programmer wishes toconstruct code to process files in (e.g.) UTF-32. This raises a questionabout newline canonicalization. My suggestion is that the port's handling of newlines should be independent of the caller. That is,read-byte on a text-mode port that would normally convert the input \r\n to \n should return the byte corresponding to \n. If you want unmangledbytes, use binary mode input. The same argument does *not* apply for read-char, because it is thenature of read-char to process the bytes in order to determine characterlength.
For a solution to these problems see SRFI 91. I would appreciate feedback on the SRFI 91 mailing list if you think it does not satisfy your needs.