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[David Oostdyk <david.oostdyk@xxxxxxxxx>]

Public bug reported:

Dash (the thing that seems to be the default /bin/bash) seems to
mishandle the following case which is easy to verify:

tail -f some_file | some_non_existant_program

Although dash correctly reports that some_non_existant_program is not
found, 'tail' will stay running until it produces output, at which the
write() will fail and tail will exit.  Other than emitting output, there
is no way to kill tail from that shell: ^C, ^Z, ^\, etc will not kill
tail; it must be killed either from another terminal or by causing it to
produce output (such as by appending to some_file).

Other shells (real bash, /bin/sh, zsh, etc.) that I have tested will
correctly kill tail immediately and will not leave the shell hanging in
an uninterruptible state.

Ubuntu 14.04 LTS

** Affects: dash (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1445544

Title:
  dash can hang when piping to a nonexistant program

Status in dash package in Ubuntu:
  New

Bug description:
  Dash (the thing that seems to be the default /bin/bash) seems to
  mishandle the following case which is easy to verify:

  tail -f some_file | some_non_existant_program

  Although dash correctly reports that some_non_existant_program is not
  found, 'tail' will stay running until it produces output, at which the
  write() will fail and tail will exit.  Other than emitting output,
  there is no way to kill tail from that shell: ^C, ^Z, ^\, etc will not
  kill tail; it must be killed either from another terminal or by
  causing it to produce output (such as by appending to some_file).

  Other shells (real bash, /bin/sh, zsh, etc.) that I have tested will
  correctly kill tail immediately and will not leave the shell hanging
  in an uninterruptible state.

  Ubuntu 14.04 LTS

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