Re: [PATCH 1/3] Detect GDB is in cygwin

[Yao Qi <yao@codesourcery.com>]

On 08/06/2013 10:08 AM, Christopher Faylor wrote:
> I'm saying that it looks like your code will detect "echo yes | gdb"
> as running on a cygwin pty.

In this case, the file name of handle looks like 
"\cygwin-c5e39b7a9d22bafb-pipe-0xBC0-0x1".  It is expected to return 
true in this case too, that is to say, we need to set stdout/stderr 
unbuffered in this case too.

In my test configuration, I use two "methods" to access remote Cygwin 
respectively, one is "ssh" and the other is "ssh -t".  We need these 
changes on stdout/stderr for these two "methods".

See the code in my patch ...

> +  /* Now check the name pattern.  With pseudo-tty allocated in ssh,
> +     the filename of handle of stdin looks like this:
> +
> +       \cygwin-c5e39b7a9d22bafb-{p,t}ty1-from-master

This is the name pattern I get if I "ssh -t" to remote Cygwin.

> +
> +     Without pseudo-tty allocated in ssh, the filename of handle of
> +     stdin looks like this:
> +
> +       \cygwin-c5e39b7a9d22bafb-pipe-0x14C8-0x3

This is the name patter I get if I "ssh" to remtoe Cygwin.

> +
> +     If the file name is prefixed with "\cygwin-", GDB is running in
> +     cygwin.  */
> +
> +  return (cp != NULL && wcsncmp (cp, L"\\cygwin-", 8) == 0);

We really need to return true for these two cases.  I find it is 
confusing to say "using pty" or "not using pty" in the comments, so I 
choose "with pty allocated" or "without pty allocated", which is much 
clear to me.

> +/* Return true if GDB is running in Cygwin pseudo-tty.  */
> +
> +int
> +using_cygwin_pty (void)

Probably you are confused by the function name and the comments.  Does 
it below help?

/* Return true if GDB is running in Cygwin.  */

int
using_cygwin (void)

-- 
Yao (齐尧)