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Corinna Vinschen <corinna-cygwin <at> cygwin.com> writes: > > IIU the SUSv4 description C, and given that a newly opened console is > always setup with the default termios settings anyway, we could simply > set O_TTY_INIT to 0 and be done with it: Yep, that's my understanding as well. This link is also informative: http://www.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap11.html#tag_11_02 "Since the termios structure may include additional members, and the standard members may include both standard and non-standard modes, the structure should never be initialized directly by the application as this may cause the terminal to behave in a non-conforming manner. When opening a terminal device (other than a pseudo-terminal) that is not already open in any process, it should be opened with the O_TTY_INIT flag before initializing the structure using tcgetattr( ) to ensure that any non-standard elements of the termios structure are set to values that result in conforming behavior of the terminal interface." In other words, tcsetattr should always be used on a struct termios obtained from a read-modify-write manner, and never from a memset(0) manner, where the use of O_TTY_INIT guarantees (trivially, if it is defined to 0) that any extension fields in struct termios that need to be set to a non-zero value for POSIX conformance are set correctly. -- Eric Blake -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
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