On Fri, 05 Oct 2018 17:32:16, Houder wrote: > On Thu, 04 Oct 2018 18:02:03, Houder wrote: > > On Wed, 03 Oct 2018 20:46:11, Houder wrote: > > > On Wed, 3 Oct 2018 15:37:14, Ole Tange wrote: > > > > This works: > > > > > > > > $ mkfifo fifo > > > > $ echo > fifo & grep . fifo > > > > [1] 10232 > > > > [1]+ Done echo > fifo > > > > > > > > But this fails: > > > > > > > > $ echo > fifo & grep . < fifo > > > > [1] 11756 > > > > grep: (standard input): Invalid argument > > > > [1]+ Done echo > fifo > > > > > > > > I see the same behavior on MINGW, but I do not see the same behavior on > > > > GNU= > > > > /Linux. > > > > My apologies. Did not read your post as careful as I should have the first > > time. > > You are correct: grep is in error here. > > Filed this bug at bug-g...@gnu.org; it is filed under number 32943. > > - https://debbugs.gnu.org/cgi/bugreport.cgi?bug=32943 >
grep fails on Cygwin because lseek() on Cygwin fails to recognize that it is applied to a FIFO. As result of that, it returns EINVAL in errno, where it should return ESPIPE. Receiving the wrong value in errno forces reset() (in src/grep.c) to return false, upon which grep fails. Before v2.27 of grep, a call to S_ISREG(st->st_mode) in reset() prevented the call of lseek() and made reset() return true. The call to S_ISREG() has been removed in v2.27 of grep. The solution would be either to correct Cygwin's executive or to insert a Cygwin-specific kludge in grep (in reset() ). Regards, Henri -- 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
