[PATCH] tee: add option for outputting to stderr

[Peter Berbec]

When writing scripts, the ability to send something to stdout and stderr 
sometimes comes up. I have written a patch to tee.c adding an option for 
this.

Peter Berbec

47a48,50
> /* If true, output to stderr as well */
> static bool out_to_error;
61a65
>   {"error", no_argument, NULL, 'e'},
92a97
>   -e, --error               also output to stderr. negates -p\n\\
132a138
>   out_to_error = false;
134c140
<   while ((optc = getopt_long (argc, argv, "aip", long_options, NULL)) != -1)
---
>   while ((optc = getopt_long (argc, argv, "aeip", long_options, NULL)) != -1)
137a144,147
>       case 'e':
>         out_to_error = true;
>         break;
162a173,175
>   if (out_to_error && output_error)
>     output_error = output_error_sigpipe;
207c220
<   descriptors = xnmalloc (nfiles + 1, sizeof *descriptors);
---
>   descriptors = xnmalloc (nfiles + (out_to_error?2:1), sizeof *descriptors);
231a245,252
>   if (out_to_error)
>     {
>       descriptors[i] = stderr;
>       files[i] = bad_cast (_("standard error"));
>       setvbuf (stderr, NULL, _IONBF, 0);
>       n_outputs++;
>     }
250a272,273
>             if (descriptors[i] == stderr)
>               clearerr (stdout); /* Avoid redundant close_stderr diagnostic.  */