make pipes non-blocking and read output on POLLHUP (#490)

this makes it so that script outputs are read when the script
actually finishes. one objection to reading on POLLHUP was that
the script might fill up the pipe and get stuck. we already mark
the read-end as non-blocking on our end so might as well make
the write-end non-blocking as well which avoids the script
getting blocked after (and if) it fills up the pipe.

ref: https://codeberg.org/nsxiv/nsxiv/pulls/334
Closes: https://codeberg.org/nsxiv/nsxiv/issues/377

Reviewed-on: https://codeberg.org/nsxiv/nsxiv/pulls/490
Reviewed-by: eylles <eylles@noreply.codeberg.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/nsxiv.h b/nsxiv.h
index 3ffc113..fc0720c 100644
--- a/nsxiv.h
+++ b/nsxiv.h
@@ -356,7 +356,7 @@ int r_closedir(r_dir_t*);
 char* r_readdir(r_dir_t*, bool);
 int r_mkdir(char*);
 void construct_argv(char**, unsigned int, ...);
-pid_t spawn(int*, int*, char *const []);
+pid_t spawn(int*, int*, int, char *const []);
 
 
 /* window.c */