> On Sep 17, 2017, at 4:53 AM, Marc Espie <es...@nerim.net> wrote: > > On Sat, Sep 16, 2017 at 10:25:19PM -0500, Scott Cheloha wrote: >> Hi, >> >> [...] >> >> -- >> Scott Cheloha >> >> Index: lib/libc/sys/write.2 >> =================================================================== >> RCS file: /cvs/src/lib/libc/sys/write.2,v >> retrieving revision 1.39 >> diff -u -p -r1.39 write.2 >> --- lib/libc/sys/write.2 5 Feb 2015 02:33:09 -0000 1.39 >> +++ lib/libc/sys/write.2 17 Sep 2017 03:02:57 -0000 >> @@ -311,7 +311,7 @@ function call appeared in >> Error checks should explicitly test for \-1. >> Code such as >> .Bd -literal -offset indent >> -while ((nr = write(fd, buf, sizeof(buf))) > 0) >> +while ((nw = write(fd, buf, sizeof(buf))) > 0) >> .Ed >> .Pp >> is not maximally portable, as some platforms allow for >> @@ -325,5 +325,5 @@ and >> may appear as a negative number distinct from \-1. >> Proper loops should use >> .Bd -literal -offset indent >> -while ((nr = write(fd, buf, sizeof(buf))) != -1 && nr != 0) >> +while ((nw = write(fd, buf, sizeof(buf))) != -1 && nw == sizeof(buf)) >> .Ed > > Well, that's not okay either, because nw == sizeof(buf) will only make > sense for file-based fds.
Ah, okay. So my third question was about partial writes. I left it out because I figured that we could just say explicitly that the examples did not cover partial writes if need be. At least, I think that's what you mean when you say that '== sizeof(buf)' only makes sense for file-based fds. > I'm for either scraping the example altogether or writing a proper > one, which would mean embedding any version of safe_write in the > man page. Could you point to an example of safe_write in the tree that covers what you're looking for? Is it akin to writeall() in signify(1) or atomicio() for nc(1)? -- Scott Cheloha
