shell - wget won't stop after the surrounding subshell is killed -

see:

(wget http://stackoverflow.com/questions/ask && echo 'ok' || echo 'failed') & pid=$! sleep 1      # curcial kill $pid 

if took out second line, there no hanging wegt after script finishes. want achieve kill wget process(or subshell whole) @ time , more processing based on exit code of wget. can explain me why wget in above script doesn't killed properly, , how make ? or there way can achieve want ?

consider following:

$ foo=foo $ export foo $ (foo=bar; echo foo $foo); echo foo $foo foo bar foo foo 

a processes doesn't change parent's environment. goes shell processes , subshells, too.

braces alter logical priority without creating subshell:

$ foo=foo $ export foo $ { foo=bar; echo foo $foo); }; echo foo $foo foo bar foo bar 

so think want

{ wget http://stackoverflow.com/questions/ask \   && echo 'ok' || echo 'failed'; } &  kill $! 

i want ... kill wget process (or subshell) ... , more processing based on exit code of wget.

i assume example simplified, , want know whether wget completed or not, , if killed. information in $!, except echo 'failed' return true. if that's issue, trap status before echoing message.