171 lines
4.0 KiB
HTML
171 lines
4.0 KiB
HTML
|
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<HTML><HEAD><TITLE>Man page of GETUNWIND</TITLE>
|
|
</HEAD><BODY>
|
|
<H1>GETUNWIND</H1>
|
|
Section: Linux Programmer's Manual (2)<BR>Updated: 2017-09-15<BR><A HREF="#index">Index</A>
|
|
<A HREF="/cgi-bin/man/man2html">Return to Main Contents</A><HR>
|
|
|
|
<A NAME="lbAB"> </A>
|
|
<H2>NAME</H2>
|
|
|
|
getunwind - copy the unwind data to caller's buffer
|
|
<A NAME="lbAC"> </A>
|
|
<H2>SYNOPSIS</H2>
|
|
|
|
<PRE>
|
|
<B>#include <<A HREF="file:///usr/include/syscall.h">syscall.h</A>></B>
|
|
<B>#include <<A HREF="file:///usr/include/linux/unwind.h">linux/unwind.h</A>></B>
|
|
|
|
<B>long getunwind(void </B><I>*buf</I><B>, size_t </B><I>buf_size</I><B>);</B>
|
|
</PRE>
|
|
|
|
<P>
|
|
|
|
<I>Note</I>:
|
|
|
|
There is no glibc wrapper for this system call; see NOTES.
|
|
<A NAME="lbAD"> </A>
|
|
<H2>DESCRIPTION</H2>
|
|
|
|
<I>Note: this function is obsolete.</I>
|
|
|
|
<P>
|
|
|
|
The
|
|
IA-64-specific
|
|
<B>getunwind</B>()
|
|
|
|
system call copies the kernel's call frame
|
|
unwind data into the buffer pointed to by
|
|
<I>buf</I>
|
|
|
|
and returns the size of the unwind data;
|
|
this data describes the gate page (kernel code that
|
|
is mapped into user space).
|
|
<P>
|
|
|
|
The size of the buffer
|
|
<I>buf</I>
|
|
|
|
is specified in
|
|
<I>buf_size</I>.
|
|
|
|
The data is copied only if
|
|
<I>buf_size</I>
|
|
|
|
is greater than or equal to the size of the unwind data and
|
|
<I>buf</I>
|
|
|
|
is not NULL;
|
|
otherwise, no data is copied, and the call succeeds,
|
|
returning the size that would be needed to store the unwind data.
|
|
<P>
|
|
|
|
The first part of the unwind data contains an unwind table.
|
|
The rest contains the associated unwind information, in no particular order.
|
|
The unwind table contains entries of the following form:
|
|
<P>
|
|
|
|
|
|
|
|
u64 start; (64-bit address of start of function)
|
|
u64 end; (64-bit address of end of function)
|
|
u64 info; (BUF-relative offset to unwind info)
|
|
|
|
|
|
<P>
|
|
|
|
An entry whose
|
|
<I>start</I>
|
|
|
|
value is zero indicates the end of the table.
|
|
For more information about the format, see the
|
|
<I>IA-64 Software Conventions and Runtime Architecture</I>
|
|
|
|
manual.
|
|
<A NAME="lbAE"> </A>
|
|
<H2>RETURN VALUE</H2>
|
|
|
|
On success,
|
|
<B>getunwind</B>()
|
|
|
|
returns the size of the unwind data.
|
|
On error, -1 is returned and
|
|
<I>errno</I>
|
|
|
|
is set to indicate the error.
|
|
<A NAME="lbAF"> </A>
|
|
<H2>ERRORS</H2>
|
|
|
|
<B>getunwind</B>()
|
|
|
|
fails with the error
|
|
<B>EFAULT</B>
|
|
|
|
if the unwind info can't be stored in the space specified by
|
|
<I>buf</I>.
|
|
|
|
<A NAME="lbAG"> </A>
|
|
<H2>VERSIONS</H2>
|
|
|
|
This system call is available since Linux 2.4.
|
|
<A NAME="lbAH"> </A>
|
|
<H2>CONFORMING TO</H2>
|
|
|
|
This system call is Linux-specific,
|
|
and is available only on the IA-64 architecture.
|
|
<A NAME="lbAI"> </A>
|
|
<H2>NOTES</H2>
|
|
|
|
This system call has been deprecated.
|
|
The modern way to obtain the kernel's unwind data is via the
|
|
<B><A HREF="/cgi-bin/man/man2html?7+vdso">vdso</A></B>(7).
|
|
|
|
<P>
|
|
|
|
Glibc does not provide a wrapper for this system call;
|
|
in the unlikely event that you want to call it, use
|
|
<B><A HREF="/cgi-bin/man/man2html?2+syscall">syscall</A></B>(2).
|
|
|
|
<A NAME="lbAJ"> </A>
|
|
<H2>SEE ALSO</H2>
|
|
|
|
<B><A HREF="/cgi-bin/man/man2html?3+getauxval">getauxval</A></B>(3)
|
|
|
|
<A NAME="lbAK"> </A>
|
|
<H2>COLOPHON</H2>
|
|
|
|
This page is part of release 5.05 of the Linux
|
|
<I>man-pages</I>
|
|
|
|
project.
|
|
A description of the project,
|
|
information about reporting bugs,
|
|
and the latest version of this page,
|
|
can be found at
|
|
<A HREF="https://www.kernel.org/doc/man-pages/.">https://www.kernel.org/doc/man-pages/.</A>
|
|
<P>
|
|
|
|
<HR>
|
|
<A NAME="index"> </A><H2>Index</H2>
|
|
<DL>
|
|
<DT id="1"><A HREF="#lbAB">NAME</A><DD>
|
|
<DT id="2"><A HREF="#lbAC">SYNOPSIS</A><DD>
|
|
<DT id="3"><A HREF="#lbAD">DESCRIPTION</A><DD>
|
|
<DT id="4"><A HREF="#lbAE">RETURN VALUE</A><DD>
|
|
<DT id="5"><A HREF="#lbAF">ERRORS</A><DD>
|
|
<DT id="6"><A HREF="#lbAG">VERSIONS</A><DD>
|
|
<DT id="7"><A HREF="#lbAH">CONFORMING TO</A><DD>
|
|
<DT id="8"><A HREF="#lbAI">NOTES</A><DD>
|
|
<DT id="9"><A HREF="#lbAJ">SEE ALSO</A><DD>
|
|
<DT id="10"><A HREF="#lbAK">COLOPHON</A><DD>
|
|
</DL>
|
|
<HR>
|
|
This document was created by
|
|
<A HREF="/cgi-bin/man/man2html">man2html</A>,
|
|
using the manual pages.<BR>
|
|
Time: 00:05:32 GMT, March 31, 2021
|
|
</BODY>
|
|
</HTML>
|