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diff --git a/man-pages-posix-2017/man3p/fattach.3p b/man-pages-posix-2017/man3p/fattach.3p new file mode 100644 index 0000000..f0b7c9e --- /dev/null +++ b/man-pages-posix-2017/man3p/fattach.3p @@ -0,0 +1,236 @@ +'\" et +.TH FATTACH "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 +fattach +\(em attach a STREAMS-based file descriptor to a file in the +file system name space (\fBSTREAMS\fP) +.SH SYNOPSIS +.LP +.nf +#include <stropts.h> +.P +int fattach(int \fIfildes\fP, const char *\fIpath\fP); +.fi +.SH DESCRIPTION +The +\fIfattach\fR() +function shall attach a STREAMS-based file descriptor to a file, +effectively associating a pathname with +.IR fildes . +The application shall ensure that the +.IR fildes +argument is a valid open file descriptor associated with a STREAMS +file. The +.IR path +argument points to a pathname of an existing file. The application +shall have appropriate privileges or be the owner of the file +named by +.IR path +and have write permission. A successful call to +\fIfattach\fR() +shall cause all pathnames that name the file named by +.IR path +to name the STREAMS file associated with +.IR fildes , +until the STREAMS file is detached from the file. A STREAMS file can be +attached to more than one file and can have several pathnames +associated with it. +.P +The attributes of the named STREAMS file shall be initialized as follows: +the permissions, user ID, group ID, and times are set to those of the +file named by +.IR path , +the number of links is set to 1, and the size and device identifier are +set to those of the STREAMS file associated with +.IR fildes . +If any attributes of the named STREAMS file are subsequently changed +(for example, by +\fIchmod\fR()), +neither the attributes of the underlying file nor the attributes of the +STREAMS file to which +.IR fildes +refers shall be affected. +.P +File descriptors referring to the underlying file, opened prior to an +\fIfattach\fR() +call, shall continue to refer to the underlying file. +.SH "RETURN VALUE" +Upon successful completion, +\fIfattach\fR() +shall return 0. Otherwise, \-1 shall be returned and +.IR errno +set to indicate the error. +.SH ERRORS +The +\fIfattach\fR() +function shall fail if: +.TP +.BR EACCES +Search permission is denied for a component of the path prefix, or the +process is the owner of +.IR path +but does not have write permissions on the file named by +.IR path . +.TP +.BR EBADF +The +.IR fildes +argument is not a valid open file descriptor. +.TP +.BR EBUSY +The file named by +.IR path +is currently a mount point or has a STREAMS file attached to it. +.TP +.BR ELOOP +A loop exists in symbolic links encountered during resolution of the +.IR path +argument. +.TP +.BR ENAMETOOLONG +.br +The length of a component of a pathname is longer than +{NAME_MAX}. +.TP +.BR ENOENT +A component of +.IR path +does not name an existing file or +.IR path +is an empty string. +.TP +.BR ENOTDIR +A component of the path prefix names an existing file that is neither +a directory nor a symbolic link to a directory, or the +.IR path +argument contains at least one non-\c +<slash> +character and ends with one or more trailing +<slash> +characters. +.TP +.BR EPERM +The effective user ID of the process is not the owner of the file named +by +.IR path +and the process does not have appropriate privileges. +.br +.P +The +\fIfattach\fR() +function may fail if: +.TP +.BR EINVAL +The +.IR fildes +argument does not refer to a STREAMS file. +.TP +.BR ELOOP +More than +{SYMLOOP_MAX} +symbolic links were encountered during resolution of the +.IR path +argument. +.TP +.BR ENAMETOOLONG +.br +The length of a pathname exceeds +{PATH_MAX}, +or pathname resolution of a symbolic link produced an intermediate +result with a length that exceeds +{PATH_MAX}. +.TP +.BR EXDEV +A link to a file on another file system was attempted. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +.SS "Attaching a File Descriptor to a File" +.P +In the following example, +.IR fd +refers to an open STREAMS file. The call to +\fIfattach\fR() +associates this STREAM with the file +.BR /tmp/named-STREAM , +such that any future calls to open +.BR /tmp/named-STREAM , +prior to breaking the attachment via a call to +\fIfdetach\fR(), +will instead create a new file handle referring to the STREAMS file +associated with +.IR fd . +.sp +.RS 4 +.nf + +#include <stropts.h> +\&... + int fd; + char *pathname = "/tmp/named-STREAM"; + int ret; +.P + ret = fattach(fd, pathname); +.fi +.P +.RE +.SH "APPLICATION USAGE" +The +\fIfattach\fR() +function behaves similarly to the traditional +\fImount\fR() +function in the way a file is temporarily replaced by the root +directory of the mounted file system. In the case of +\fIfattach\fR(), +the replaced file need not be a directory and the replacing file is a +STREAMS file. +.SH RATIONALE +The file attributes of a file which has been the subject of an +\fIfattach\fR() +call are specifically set because of an artifact of the original +implementation. The internal mechanism was the same as for the +\fImount\fR() +function. Since +\fImount\fR() +is typically only applied to directories, the effects when applied to +a regular file are a little surprising, especially as regards the link +count which rigidly remains one, even if there were several links +originally and despite the fact that all original links refer to the +STREAM as long as the +\fIfattach\fR() +remains in effect. +.SH "FUTURE DIRECTIONS" +The +\fIfattach\fR() +function may be removed in a future version. +.SH "SEE ALSO" +.IR "\fIfdetach\fR\^(\|)", +.IR "\fIisastream\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<stropts.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 . |