In the bad old days, not every thing was documented ... My use of scm_puts dates back to guile-1.8. I only ever send it utf8. I can change my code, no problem,... I just thought I'd report a regression in case .... others are affected. Linas On Wednesday, March 1, 2017, Andy Wingo wrote: > On Tue 10 Jan 2017 04:34, Linas Vepstas > writes: > > > void *wrap_puts(void* p) > > { > > char *wtf = p; > > > > SCM port = scm_current_output_port (); > > > > scm_puts("the port-encoding is=", port); > > scm_puts(scm_to_utf8_string(scm_port_encoding(port)), port); > > > > scm_puts("\nThe string to display is =", port); > > scm_puts (wtf, port); > > > > scm_puts("\nWas expecting to see this=", port); > > SCM str = scm_from_utf8_string(wtf); > > scm_display(str, port); > > scm_puts("\n\n", port); > > > > return NULL; > > } > > So, there are a few questions here. scm_puts and scm_lfwrite are not > documented, so we need to do basic science on them to see what they are > supposed to do. > > Firstly, is scm_puts() a textual interface or a binary interface? > I.e. does it write a sequence of characters or a sequence of bytes? > > If I look at uses of scm_puts in Guile sources, it seems clear that it's > a textual interface. That is to say, at all points, the intention seems > to be to write characters on a Guile port. All of the uses are of > strings. Please do a "git grep" on your source to see if your > perceptions correspond. > > Now the question is, what encoding is the argument in? If the port is > UTF-16, that byte string should be decoded to characters, and that > character sequence encoded to UTF-16. > > All of the scm_puts calls in Guile are of one-byte characters with > codepoints less than 128, so when doing some port refactoring I chose to > interpret the argument as latin1. > > FTR, in Guile 2.0, this was effectively a binary interface. Guile 2.0's > scm_lfwrite interpreted the incoming bytes as ISO-8859-1 codepoints for > the purposes of updating line and column, but scm_puts and scm_lfwrite > just wrote out the bytes to the port directly, regardless of the > encoding. That was the wrong thing. > > Are you arguing that the byte string given to scm_puts should be decoded > from UTF-8? That would be OK. > > Andy >