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diff --git a/man-pages-posix-2013/man3p/tcgetattr.3p b/man-pages-posix-2013/man3p/tcgetattr.3p new file mode 100644 index 0000000..6510980 --- /dev/null +++ b/man-pages-posix-2013/man3p/tcgetattr.3p @@ -0,0 +1,146 @@ +'\" et +.TH TCGETATTR "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +tcgetattr +\(em get the parameters associated with the terminal +.SH SYNOPSIS +.LP +.nf +#include <termios.h> +.P +int tcgetattr(int \fIfildes\fP, struct termios *\fItermios_p\fP); +.fi +.SH DESCRIPTION +The +\fItcgetattr\fR() +function shall get the parameters associated with the terminal referred +to by +.IR fildes +and store them in the +.BR termios +structure referenced by +.IR termios_p . +The +.IR fildes +argument is an open file descriptor associated with a terminal. +.P +The +.IR termios_p +argument is a pointer to a +.BR termios +structure. +.P +The +\fItcgetattr\fR() +operation is allowed from any process. +.P +If the terminal device supports different input and output baud rates, +the baud rates stored in the +.BR termios +structure returned by +\fItcgetattr\fR() +shall reflect the actual baud rates, even if they are equal. If +differing baud rates are not supported, the rate returned as the output +baud rate shall be the actual baud rate. If the terminal device does +not support split baud rates, the input baud rate stored in the +.BR termios +structure shall be the output rate (as one of the symbolic values). +.SH "RETURN VALUE" +Upon successful completion, 0 shall be returned. Otherwise, \(mi1 +shall be returned and +.IR errno +set to indicate the error. +.SH ERRORS +The +\fItcgetattr\fR() +function shall fail if: +.TP +.BR EBADF +The +.IR fildes +argument is not a valid file descriptor. +.TP +.BR ENOTTY +The file associated with +.IR fildes +is not a terminal. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +Care must be taken when changing the terminal attributes. Applications +should always do a +\fItcgetattr\fR(), +save the +.BR termios +structure values returned, and then do a +\fItcsetattr\fR(), +changing only the necessary fields. The application should use the +values saved from the +\fItcgetattr\fR() +to reset the terminal state whenever it is done with the terminal. +This is necessary because terminal attributes apply to the underlying +port and not to each individual open instance; that is, all processes +that have used the terminal see the latest attribute changes. +.P +A program that uses these functions should be written to catch all +signals and take other appropriate actions to ensure that when the +program terminates, whether planned or not, the terminal device's state +is restored to its original state. +.P +Existing practice dealing with error returns when only part of a +request can be honored is based on calls to the +\fIioctl\fR() +function. In historical BSD and System V implementations, +the corresponding +\fIioctl\fR() +returns zero if the requested actions were semantically correct, even +if some of the requested changes could not be made. Many existing +applications assume this behavior and would no longer work correctly if +the return value were changed from zero to \(mi1 in this case. +.P +Note that either specification has a problem. When zero is returned, +it implies everything succeeded even if some of the changes were not +made. When \(mi1 is returned, it implies everything failed even though +some of the changes were made. +.P +Applications that need all of the requested changes made to work +properly should follow +\fItcsetattr\fR() +with a call to +\fItcgetattr\fR() +and compare the appropriate field values. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fItcsetattr\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "Chapter 11" ", " "General Terminal Interface", +.IR "\fB<termios.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |