Re: minor bug in bash

[Zachary Miller]

On Tue, Jan 17, 2012 at 10:18:00PM -0500, Chet Ramey wrote:
> On 1/17/12 10:05 PM, Zachary Miller wrote:
> >> Thanks for the report.  As a practical matter, this doesn't present a
> >> problem.  When writing to a regular file, with no special flags supplied
> >> to open(), the only cases Posix says it can return fewer bytes than
> >> specified are errors.
> > 
> > thank chet.  i figured that may be the case.  if you wouldn't mind, could 
> > you
> > point me to where exactly that behavior is documented?
> 
> Sure.  That's how I read
> 
> http://pubs.opengroup.org/onlinepubs/9699919799/functions/write.html#tag_16_879

thank you.  for me, this is the line at issue:

  If write() is interrupted by a signal after it successfully writes some data, 
it shall return the number of bytes written.

consider SIGSTOP, which is non-maskable.  when the process continues, wouldn't
this be a situation where the write was interrupted and thus could legitimately
return fewer bytes?

(btw, i agree that as a practical matter, this probably isn't anything to worry
 about, but i'm curious how others view this theoretical situation)


cheers,
-zach