Hi Pali,
On 7/30/21 11:53 AM, Pali Rohár wrote:
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
Thanks for the patch!
Please see some comments below.
Cheers,
Alex
---
man2/ioctl_tty.2 | 60 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
diff --git a/man2/ioctl_tty.2 b/man2/ioctl_tty.2
index 0b0083c671a7..9d394572ae93 100644
--- a/man2/ioctl_tty.2
+++ b/man2/ioctl_tty.2
@@ -750,6 +750,66 @@ main(void)
close(fd);
}
.EE
+.PP
+Get or set arbitrary baudrate on the serial port.
+.PP
+.EX
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <asm/termbits.h>
Unless there's a reason to use a specific include order (and if so, add
a comment), please use alphabetical order.
+
+int
+main(int argc, char *argv[])
+{
+#if !defined(TCGETS2) || !defined(TCSETS2) || !defined(BOTHER)
+ fprintf(stderr, "TCGETS2, TCSETS2 or BOTHER is unsupported\\n");
+ return 1;
+#else
Do we want the program to compile if those are unsupported?
Maybe you can #error there and simplify the reader having to parse the
preprocessor directive mentally:
#if !defined...
# error ...
#endif
I know it's non-standard, but I think it's common enough so that we can
use it here.
+ struct termios2 tio2;
+ int fd, rc;
+
+ if (argc != 2 && argc != 3) {
+ fprintf(stderr, "Usage: %s device [new_baudrate]\\n", argv[0]);
We use \e for printing the escape character. Not \\
CC: Branden
See groff_man(7):
Portability
[...]
Similar caveats apply to escapes. Some escape sequences
are however required for correct typesetting even in man
pages and usually do not cause portability problems:
[...]
\e Widely used in man pages to represent a backslash
output glyph. It works reliably as long as the .ec
request is not used, which should never happen in
man pages, and it is slightly more portable than the
more exact ‘\(rs’ (“reverse solidus”) escape se‐
quence.
+ return 1;
+ }
+
+ fd = open(argv[1], O_RDWR | O_NONBLOCK | O_NOCTTY);
+ if (fd < 0) {
+ perror("open");
+ return 1;
exit(EXIT_FAILURE);
+ }
+
+ rc = ioctl(fd, TCGETS2, &tio2);
+ if (rc) {
+ perror("TCGETS2");
+ close(fd);
+ return 1;
exit(3)
+ }
+
+ printf("%u\\n", tio2.c_ospeed);
\e
+
+ if (argc == 3) {
+ tio2.c_cflag &= ~CBAUD;
+ tio2.c_cflag |= BOTHER;
+ tio2.c_ospeed = tio2.c_ispeed = atoi(argv[2]);
+
+ rc = ioctl(fd, TCSETS2, &tio2);
+ if (rc) {
+ perror("TCSETS2");
+ close(fd);
+ return 1;
exit(3)
+ }
+ }
+
+ close(fd);
+ return 0;
exit(3)
+#endif
+}
+.EE
.SH SEE ALSO
.BR ldattach (1),
.BR ioctl (2),
--
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/
