examples/functions/coshell.README

   1 Date: Fri, 21 Sep 2001 14:50:29 -0400
   2 From: "Jason M. Felice" <jfelice@cronosys.com>
   3 To: bash-maintainers@gnu.org, chet@po.cwru.edu
   4 Subject: Bash co-processes functions
   5 Message-ID: <20010921145029.A6093@argo.eraserhead.net>
   6 Mime-Version: 1.0
   7
   8 Attached to this message you will find coprocess.bash and coshell.bash.
   9 Here's a brief synopsis of use:
  10
  11 coprocess open telnet localhost
  12 while coprocess read il ; do
  13   echo "$il"
  14   case "$il" in
  15     *ogin:*)
  16       coprocess print 'user'
  17       ;;
  18     *ord:*)
  19       echo 'pass' |coprocess print --stdin
  20       ;;
  21     *$ *)
  22       coprocess print 'exit'
  23       break
  24       ;;
  25   esac
  26 done
  27 coprocess close
  28
  29 And here's an example of the coshell function:
  30
  31 coshell open ssh -l root otherbox
  32 coshell eval hostname
  33 coshell ls -l
  34 if coshell test -d /tmp ; then echo 'otherbox has a /tmp!' ; fi
  35
  36 coshell sendfile /var/lib/upgrade.rpm /tmp/test.rpm || exit $?
  37 coshell eval rpm -ivh /tmp/test.rpm || exit $?
  38 coshell eval rm -f /tmp/test.rpm || exit $?
  39 coshell close
  40 exit 0
  41
  42 There are a few minor issues that I'd like to work out, but it works well
  43 enough for me ;-)  The issues are:
  44
  45 - Shell quoting issue with 'coshell eval' commands - need to somehow
  46   re-quote words.
  47 - Interactive commands hang 'coshell eval', tried redirecting in </dev/null
  48   to executed command, but it caused strange shell exit problems.
  49 - Some way to copy stdin from local coshell eval to remote shell.  Probably
  50   logically impossible, but would be wonderfully useful.
  51
  52 I'm using it for writing scripts to publish websites and other scripts to
  53 co-located servers.