On 2017-06-13 08:11, cyg Simple wrote: > On 6/10/2017 10:30 PM, Eric Blake wrote: >> On 06/10/2017 08:48 AM, cyg Simple wrote: >>> Uhm, 'wt' and 'wb' came from MS itself. >> Not quite. fopen(,"wb") comes from POSIX. "wt" is probably a microsoft >> extension, but it is certainly not in POSIX nor in glibc. > I think it's a C standard so it should be in glibc. It may be mentioned > in the POSIX standard as in support of the C standard. >>> GNU GCC was adapted to allow it >> Huh? It's not whether the compiler allows it, but whether libc allows >> it. ALL libc that are remotely close to POSIX compliant support >> fopen(,"wb"), but only Windows platforms (and NOT glibc) support >> fopen(,"wt"). > Looking at http://www.cplusplus.com/reference/cstdio/fopen/ I see: > "If additional characters follow the sequence, the behavior depends on > the library implementation: some implementations may ignore additional > characters so that for example an additional "t" (sometimes used to > explicitly state a text file) is accepted." > There is also a lot of discussion about the topic at: > https://stackoverflow.com/questions/229924/difference-between-files-writen-in-binary-and-text-mode > As for glibc, it will just ignore the extra character but it allows the > use of "wt"; it just means nothing to that C runtime library. It does > aide in portable code though. > As for me conflating GCC with a C runtime - please forgive my lapse in > memory.
There's no need for open mode "t", as text is the default mode unless "b" is specified, and assuming you use "cooked" line I/O functions like fgets/fputs, not "raw" binary I/O like fread/fwrite; fscanf ignores all line terminators unless you use formats like "%c" which could see them. -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
