tidy up O_NONBLOCK usage. use libbb functions in stty.

Added O_RDONLY where improves readability. Note: O_RDONLY == 0,
so it is there even if not specified.

function                                             old     new   delta
stty_main                                           1289    1235     -54

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2009-11-11 21:05:42 +01:00
parent c096a6c208
commit ab19ede655
7 changed files with 12 additions and 22 deletions

View File

@@ -39,18 +39,18 @@ ssize_t FAST_FUNC safe_read(int fd, void *buf, size_t count)
* *** BIG SURPRISE! It stays even after child exits! ***
*
* This is a design bug in UNIX API.
* fcntl(0, F_SETFL, fcntl(0, F_GETFL, 0) | O_NONBLOCK);
* fcntl(0, F_SETFL, fcntl(0, F_GETFL) | O_NONBLOCK);
* will set nonblocking mode not only on _your_ stdin, but
* also on stdin of your parent, etc.
*
* In general,
* fd2 = dup(fd1);
* fcntl(fd2, F_SETFL, fcntl(fd2, F_GETFL, 0) | O_NONBLOCK);
* fcntl(fd2, F_SETFL, fcntl(fd2, F_GETFL) | O_NONBLOCK);
* sets both fd1 and fd2 to O_NONBLOCK. This includes cases
* where duping is done implicitly by fork() etc.
*
* We need
* fcntl(fd2, F_SETFD, fcntl(fd2, F_GETFD, 0) | O_NONBLOCK);
* fcntl(fd2, F_SETFD, fcntl(fd2, F_GETFD) | O_NONBLOCK);
* (note SETFD, not SETFL!) but such thing doesn't exist.
*
* Alternatively, we need nonblocking_read(fd, ...) which doesn't