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diff --git a/upstream/archlinux/man3p/ctermid.3p b/upstream/archlinux/man3p/ctermid.3p new file mode 100644 index 00000000..503f0505 --- /dev/null +++ b/upstream/archlinux/man3p/ctermid.3p @@ -0,0 +1,148 @@ +'\" et +.TH CTERMID "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 +ctermid +\(em generate a pathname for the controlling terminal +.SH SYNOPSIS +.LP +.nf +#include <stdio.h> +.P +char *ctermid(char *\fIs\fP); +.fi +.SH DESCRIPTION +The +\fIctermid\fR() +function shall generate a string that, when used as a pathname, +refers to the current controlling terminal for the current process. If +\fIctermid\fR() +returns a pathname, access to the file is not guaranteed. +.P +The +\fIctermid\fR() +function need not be thread-safe if called with a NULL parameter. +.SH "RETURN VALUE" +If +.IR s +is a null pointer, the string shall be generated in an area that may be +static, the address of which shall be returned. The application shall +not modify the string returned. The returned pointer might be invalidated +or the string content might be overwritten by a subsequent call to +\fIctermid\fR(). +The returned pointer might also be invalidated if the calling thread +is terminated. +If +.IR s +is not a null pointer, +.IR s +is assumed to point to a character array of at least L_ctermid bytes; +the string is placed in this array and the value of +.IR s +shall be returned. The symbolic constant L_ctermid is defined in +.IR <stdio.h> , +and shall have a value greater than 0. +.P +The +\fIctermid\fR() +function shall return an empty string if the pathname that would refer +to the controlling terminal cannot be determined, or if the function is +unsuccessful. +.SH ERRORS +No errors are defined. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +.SS "Determining the Controlling Terminal for the Current Process" +.P +The following example returns a pointer to a string that identifies the +controlling terminal for the current process. The pathname for the +terminal is stored in the array pointed to by the +.IR ptr +argument, which has a size of L_ctermid bytes, as indicated by the +.IR term +argument. +.sp +.RS 4 +.nf + +#include <stdio.h> +\&... +char term[L_ctermid]; +char *ptr; +.P +ptr = ctermid(term); +.fi +.P +.RE +.SH "APPLICATION USAGE" +The difference between +\fIctermid\fR() +and +\fIttyname\fR() +is that +\fIttyname\fR() +must be handed a file descriptor and return a path of the terminal +associated with that file descriptor, while +\fIctermid\fR() +returns a string (such as +.BR \(dq/dev/tty\(dq ) +that refers to the current controlling terminal if used as a +pathname. +.SH RATIONALE +L_ctermid +must be defined appropriately for a given implementation and must be +greater than zero so that array declarations using it are accepted by +the compiler. The value includes the terminating null byte. +.P +Conforming applications that use multiple threads cannot call +\fIctermid\fR() +with NULL as the parameter. If +.IR s +is not NULL, the +\fIctermid\fR() +function generates a string that, when used as a pathname, refers to +the current controlling terminal for the current process. If +.IR s +is NULL, the return value of +\fIctermid\fR() +is undefined. +.P +There is no additional burden on the programmer\(emchanging to use a +hypothetical thread-safe version of +\fIctermid\fR() +along with allocating a buffer is more of a burden than merely +allocating a buffer. Application code should not assume that the +returned string is short, as some implementations have more than two +pathname components before reaching a logical device name. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIttyname\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<stdio.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 . |