.\" Copyright 2015-2017 IBM Corp.
.\"
.TH CXL_ERRINFO_READ 3 2017-05-24 "LIBCXL 1.5" "CXL Programmer's Manual"
.SH NAME
cxl_errinfo_read \- Read and copy the contents of afu_err_info buffer
.SH SYNOPSIS
.BR #include <libcxl.h>
.PP
.BI "ssize_t cxl_errinfo_read(struct cxl_afu_h "
.BI * afu ", void *" dst ", off_t " off ", size_t " len );
.SH DESCRIPTION
.PP
.BR cxl_errinfo_read " attempts to read upto"
.IR len " bytes located at offset " off " in "
AFU Error Buffer and copy it to user provided buffer located at
.IR dst "."
.PP
AFU Error Buffer is used by the afu to report
application specific errors.
The contents of this buffer are afu
specific and are intended to be interpreted by the application
interacting with the afu.
.SH RETURN VALUE
On success, returns the number of bytes copied from the afu_err_buff to
.IB dst .

On error, -1 is returned,
.I errno
is set appropriately and the contents at
.I dst
are not touched.
.SH ERRORS
.TP
.B ENOENT
The AFU does not export afu_err_buff region.
.TP
.B EACCES
Permission to read the contents of AFU Error buffer is denied.
.TP
.B ENOMEM
Insufficient memory.
.TP
.B ENOSPC
No AFU context available.
.TP
.B EPROTO
Unsupported kernel CXL API version.
.SH FILES
.TP
.BI /dev/cxl/afu <i> . <j> d
AFU device in dedicated process mode.
.TP
.BI /dev/cxl/afu <i> . <j> m
AFU device in AFU directed mode, master context.
.TP
.BI /dev/cxl/afu <i> . <j> s
AFU device in AFU directed mode, slave context.
.TP
.BI /dev/cxl/afu <i> . <j> /afu_err_buff
AFU Error Buffer contents. The contents of this file are
application specific and depends on the AFU being used.

.SH SEE ALSO
.BR cxl (3),
.BR cxl_errinfo_size (3)