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diff --git a/man3p/seekdir.3p b/man3p/seekdir.3p new file mode 100644 index 000000000..0b5f72737 --- /dev/null +++ b/man3p/seekdir.3p @@ -0,0 +1,83 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "SEEKDIR" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" seekdir +.SH NAME +seekdir \- set the position of a directory stream +.SH SYNOPSIS +.LP +\fB#include <dirent.h> +.br +.sp +void seekdir(DIR *\fP\fIdirp\fP\fB, long\fP \fIloc\fP\fB); \fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fIseekdir\fP() function shall set the position of the next \fIreaddir\fP() +operation on the directory stream specified by \fIdirp\fP to the position +specified by \fIloc\fP. The value of \fIloc\fP should +have been returned from an earlier call to \fItelldir\fP(). The new +position reverts to +the one associated with the directory stream when \fItelldir\fP() +was performed. +.LP +If the value of \fIloc\fP was not obtained from an earlier call to +\fItelldir\fP(), or +if a call to \fIrewinddir\fP() occurred between the call to \fItelldir\fP() +and the call to \fIseekdir\fP(), the results of subsequent calls to +\fIreaddir\fP() are unspecified. +.SH RETURN VALUE +.LP +The \fIseekdir\fP() function shall not return a value. +.SH ERRORS +.LP +No errors are defined. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +None. +.SH RATIONALE +.LP +The original standard developers perceived that there were restrictions +on the use of the \fIseekdir\fP() and \fItelldir\fP() functions related +to implementation details, and for that reason these functions +need not be supported on all POSIX-conforming systems. They are required +on implementations supporting the XSI extension. +.LP +One of the perceived problems of implementation is that returning +to a given point in a directory is quite difficult to describe +formally, in spite of its intuitive appeal, when systems that use +B-trees, hashing functions, or other similar mechanisms to order +their directories are considered. The definition of \fIseekdir\fP() +and \fItelldir\fP() +does not specify whether, when using these interfaces, a given directory +entry will be seen at all, or more than once. +.LP +On systems not supporting these functions, their capability can sometimes +be accomplished by saving a filename found by \fIreaddir\fP() and +later using \fIrewinddir\fP() and a +loop on \fIreaddir\fP() to relocate the position from which the filename +was saved. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIopendir\fP() , \fIreaddir\fP() , \fItelldir\fP() , the Base Definitions +volume of IEEE\ Std\ 1003.1-2001, \fI<dirent.h>\fP, \fI<stdio.h>\fP, +\fI<sys/types.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 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 . |