bin/48285: atf-sh-api(1) atf_check examples don't work

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         48285
>Category:       bin
>Synopsis:       atf_check examples in atf-sh-api(1) don't work
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          doc-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Oct 07 11:10:00 +0000 2013
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date 2013.08.04.11.02.02
>Organization:
>Environment:
System: NetBSD
Architecture: i386
Machine: i386
>Description:

The atf-sh-api(1) man page says:

     This example demonstrates the use of the very useful atf_check()
     function:

           # Check for silent output
           atf_check 'true' 0 null null

           # Check for silent output and failure
           atf_check 'false' 1 null null

           # Check for known stdout and silent stderr
           echo foo >expout
           atf_check 'echo foo' 0 expout null

but if you acutally try to use that syntax in a test program,
it doesn't work.  For example, with

    atf_check 'echo foo' 0 expout null

you get:

  tc-se:execvp(echo foo) failed: No such file or directory

>How-To-Repeat:

man atf-sh-api

>Fix: