diff options
| -rw-r--r-- | byterun/io.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/byterun/io.c b/byterun/io.c index 50b5b149b..0c3f22dec 100644 --- a/byterun/io.c +++ b/byterun/io.c @@ -122,11 +122,13 @@ again: if (retcode == -1) { if (errno == EINTR) goto again; if (errno == EAGAIN || errno == EWOULDBLOCK) { - /* POSIX says that a write on a pipe in non-blocking mode may return - EAGAIN if it attempts to write more than PIPE_BUF characters, - PIPE_BUF being at least 512. In this case, we try again with - strictly less than PIPE_BUF characters. */ - if (n >= 512) { n = 256; goto again; } + /* We couldn't do a partial write here, probably because + n <= PIPE_BUF and POSIX says that writes of less than + PIPE_BUF characters must be atomic. + So, we force a partial write of 1 character. + This should always succeed if we've done a select + on writing just before. */ + if (n > 1) { n = 1; goto again; } } } #endif |