docs/167201: manpage pread(2) misses one error case (EBUSY)

[Kurt Jaeger]

>Number:         167201
>Category:       docs
>Synopsis:       manpage pread(2) misses one error case (EBUSY)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-doc
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          doc-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Apr 22 13:00:27 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Kurt Jaeger
>Release:        FreeBSD 8.3-RELEASE amd64
>Organization:
-
>Environment:
System: FreeBSD fa8.opsec.eu 8.3-RELEASE FreeBSD 8.3-RELEASE #0: Mon Apr 9 21:23:18 UTC 2012 root at mason.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64


>Description:
	a call to pread might fail with EBUSY in certain cases,
	and that error is not in the man page.
>How-To-Repeat:
	ports/devel/strace uses pread and fails because of this
>Fix:

--- pread.2-orig	2012-04-22 14:52:55.000000000 +0200
+++ pread.2	2012-04-22 14:52:29.000000000 +0200
@@ -164,6 +164,8 @@
 points outside the allocated address space.
 .It Bq Er EIO
 An I/O error occurred while reading from the file system.
+.It Bq Er EBUSY
+Failed to read from a file, e.g. /proc/<pid>/regs while <pid> is not stopped
 .It Bq Er EINTR
 A read from a slow device
 (i.e.\& one that might block for an arbitrary amount of time)

>Release-Note:
>Audit-Trail:
>Unformatted: