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+'\" et
+.TH TCGETATTR "3P" 2017 "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, \-1
+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 \-1 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 \-1 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\(hy2017,
+.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 1003.1-2017, Standard for Information Technology
+-- Portable Operating System Interface (POSIX), The Open Group Base
+Specifications Issue 7, 2018 Edition,
+Copyright (C) 2018 by the Institute of
+Electrical and Electronics Engineers, Inc and The Open Group.
+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.opengroup.org/unix/online.html .
+.PP
+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 .