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diff --git a/man-pages-posix-2013/man3p/posix_openpt.3p b/man-pages-posix-2013/man3p/posix_openpt.3p new file mode 100644 index 0000000..24668b6 --- /dev/null +++ b/man-pages-posix-2013/man3p/posix_openpt.3p @@ -0,0 +1,172 @@ +'\" et +.TH POSIX_OPENPT "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 +posix_openpt +\(em open a pseudo-terminal device +.SH SYNOPSIS +.LP +.nf +#include <stdlib.h> +#include <fcntl.h> +.P +int posix_openpt(int \fIoflag\fP); +.fi +.SH DESCRIPTION +The +\fIposix_openpt\fR() +function shall establish a connection between a master device for a +pseudo-terminal and a file descriptor. The file descriptor is used by +other I/O functions that refer to that pseudo-terminal. +.P +The file status flags and file access modes of the open file +description shall be set according to the value of +.IR oflag . +.P +Values for +.IR oflag +are constructed by a bitwise-inclusive OR of flags from the following +list, defined in +.IR <fcntl.h> : +.IP O_RDWR 12 +Open for reading and writing. +.IP O_NOCTTY 12 +If set +\fIposix_openpt\fR() +shall not cause the terminal device to become the controlling terminal +for the process. +.P +The behavior of other values for the +.IR oflag +argument is unspecified. +.SH "RETURN VALUE" +Upon successful completion, the +\fIposix_openpt\fR() +function shall open a master pseudo-terminal device and return a +non-negative integer representing the lowest numbered unused file +descriptor. Otherwise, \(mi1 shall be returned and +.IR errno +set to indicate the error. +.SH ERRORS +The +\fIposix_openpt\fR() +function shall fail if: +.TP +.BR EMFILE +All file descriptors available to the process are currently open. +.TP +.BR ENFILE +The maximum allowable number of files is currently open in the system. +.P +The +\fIposix_openpt\fR() +function may fail if: +.TP +.BR EINVAL +The value of +.IR oflag +is not valid. +.TP +.BR EAGAIN +Out of pseudo-terminal resources. +.TP +.BR ENOSR +Out of STREAMS resources. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +.SS "Opening a Pseudo-Terminal and Returning the Name of the Slave Device and a File Descriptor" +.sp +.RS 4 +.nf +\fB +#include <fcntl.h> +#include <stdio.h> +.P +int masterfd, slavefd; +char *slavedevice; +.P +masterfd = posix_openpt(O_RDWR|O_NOCTTY); +.P +if (masterfd == -1 + || grantpt (masterfd) == -1 + || unlockpt (masterfd) == -1 + || (slavedevice = ptsname (masterfd)) == NULL) + return -1; +.P +printf("slave device is: %s\en", slavedevice); +.P +slavefd = open(slavedevice, O_RDWR|O_NOCTTY); +if (slavefd < 0) + return -1; +.fi \fR +.P +.RE +.SH "APPLICATION USAGE" +This function is a method for portably obtaining a file descriptor of a +master terminal device for a pseudo-terminal. The +\fIgrantpt\fR() +and +\fIptsname\fR() +functions can be used to manipulate mode and ownership permissions, and +to obtain the name of the slave device, respectively. +.SH RATIONALE +The standard developers considered the matter of adding a special +device for cloning master pseudo-terminals: the +.BR /dev/ptmx +device. However, consensus could not be reached, and it was felt that +adding a new function would permit other implementations. The +\fIposix_openpt\fR() +function is designed to complement the +\fIgrantpt\fR(), +\fIptsname\fR(), +and +\fIunlockpt\fR() +functions. +.P +On implementations supporting the +.BR /dev/ptmx +clone device, opening the master device of a pseudo-terminal is simply: +.sp +.RS 4 +.nf +\fB +mfdp = open("/dev/ptmx", oflag ); +if (mfdp < 0) + return -1; +.fi \fR +.P +.RE +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIgrantpt\fR\^(\|)", +.IR "\fIopen\fR\^(\|)", +.IR "\fIptsname\fR\^(\|)", +.IR "\fIunlockpt\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<fcntl.h>\fP", +.IR "\fB<stdlib.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 . |