diff options
| -rw-r--r-- | eclass/multiprocessing.eclass | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/eclass/multiprocessing.eclass b/eclass/multiprocessing.eclass index 70ca475a8c72..67f7e2d65b42 100644 --- a/eclass/multiprocessing.eclass +++ b/eclass/multiprocessing.eclass @@ -139,11 +139,16 @@ multijob_init() { # Setup a pipe for children to write their pids to when they finish. # We have to allocate two fd's because POSIX has undefined behavior - # when you open a FIFO for simultaneous read/write. #487056 + # when using one single fd for both read and write. #487056 + # However, opening an fd for read or write only will block until the + # opposite end is opened as well. Thus we open the first fd for both + # read and write to not block ourselve, but use it for reading only. + # The second fd really is opened for write only, as Cygwin supports + # just one single read fd per FIFO. #583962 local pipe="${T}/multijob.pipe" mkfifo -m 600 "${pipe}" - redirect_alloc_fd mj_write_fd "${pipe}" redirect_alloc_fd mj_read_fd "${pipe}" + redirect_alloc_fd mj_write_fd "${pipe}" '>' rm -f "${pipe}" # See how many children we can fork based on the user's settings. |