When /dev/fd is missing, and named pipes are used instead (like on AIX),
this snippet sometimes does work right, wrong, or hang - depending on
the operating system's process scheduler timing:
for x in {0..9}; do echo $x; done > >(
cnt=0; while read line; do let cnt=cnt+1; done; echo $cnt
)
To reproduce this problem on Linux, add this line to subst.c to enforce
the problematic timing behaviour:
#if !defined (HAVE_DEV_FD)
+ sleep(1);
fifo_list[nfifo-1].proc = pid;
#endif
and enforce using named pipes: bash_cv_dev_fd=absent ./configure ...
---
subst.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/subst.c b/subst.c
index 48c89c1..afae3b7 100644
--- a/subst.c
+++ b/subst.c
@@ -5075,7 +5075,7 @@ process_substitute (string, open_for_read_in_child)
#if !defined (HAVE_DEV_FD)
/* Open the named pipe in the child. */
- fd = open (pathname, open_for_read_in_child ? O_RDONLY|O_NONBLOCK :
O_WRONLY);
+ fd = open (pathname, open_for_read_in_child ? O_RDONLY : O_WRONLY);
if (fd < 0)
{
/* Two separate strings for ease of translation. */
--
1.8.1.5
