SerialImp.c:RXTXCommDriver(testRead) - fcntl(,F_SETFL, O_RDWR) does not work on Linux #257
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…ot work on Linux On linux F_SETFL cannot change O_RDONLY, O_WRONLY, O_RDWR - https://man7.org/linux/man-pages/man2/F_GETFL.2const.html. FD_CLOEXEC is supposed to be altered by F_SETFD, not by F_SETFL - https://man7.org/linux/man-pages/man2/f_setfd.2const.html and it is not a command by its own (second parameter of fctnl) but a parameter (third parameter). Actually the definitions in usr/include/bits/fcntl-linux.h are: fcntl-linux.h:#define FD_CLOEXEC 1 /* Actually anything with low bit set goes */ fcntl-linux.h:#define F_GETFD 1 /* Get file descriptor flags. */ so int cmd=FD_CLOEXEC|F_SETFL; ret= fcntl(fd,cmd,O_RDWR | O_NOCTTY | O_NONBLOCK); was doing ret= fcntl(fd, F_GETFD | F_SETFL ,O_RDWR | O_NOCTTY | O_NONBLOCK);
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…ot work on Linux NeuronRobotics#257 On linux F_SETFL cannot change O_RDONLY, O_WRONLY, O_RDWR - https://man7.org/linux/man-pages/man2/F_GETFL.2const.html. FD_CLOEXEC is supposed to be altered by F_SETFD, not by F_SETFL - https://man7.org/linux/man-pages/man2/f_setfd.2const.html and it is not a command by its own (second parameter of fctnl) but a parameter (third parameter). Actually the definitions in usr/include/bits/fcntl-linux.h are: fcntl-linux.h:#define FD_CLOEXEC 1 /* Actually anything with low bit set goes */ fcntl-linux.h:#define F_GETFD 1 /* Get file descriptor flags. */ so int cmd=FD_CLOEXEC|F_SETFL; ret= fcntl(fd,cmd,O_RDWR | O_NOCTTY | O_NONBLOCK); was doing ret= fcntl(fd, F_GETFD | F_SETFL ,O_RDWR | O_NOCTTY | O_NONBLOCK);
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On linux F_SETFL cannot change O_RDONLY, O_WRONLY, O_RDWR - https://man7.org/linux/man-pages/man2/F_GETFL.2const.html.
FD_CLOEXEC is supposed to be altered by F_SETFD, not by F_SETFL - https://man7.org/linux/man-pages/man2/f_setfd.2const.html and it is not a command by its own (second parameter of fctnl) but a parameter (third parameter of fctnl)).
Actually the definitions in /usr/include/bits/fcntl-linux.h are:
so
was doing