[util] Remove line buffering

Something weird seems to be going on. Just kill it.

Fixes https://github.com/harfbuzz/harfbuzz/issues/888

configure.ac

@@ -79,7 +79,7 @@ GTK_DOC_CHECK([1.15],[--flavour no-tmpl])
 
 # Functions, and headers
 
-AC_CHECK_FUNCS(atexit mprotect sysconf getpagesize mmap isatty newlocale strtod_l setlinebuf)
+AC_CHECK_FUNCS(atexit mprotect sysconf getpagesize mmap isatty newlocale strtod_l)
 
 save_libs="$LIBS"
 LIBS="$LIBS -lm"

util/options.cc

@@ -803,12 +803,6 @@ text_options_t::get_line (unsigned int *len)
     gs = g_string_new (nullptr);
   }
 
-#ifdef HAVE_SETLINEBUF
-  setlinebuf (fp);
-#else
-  setvbuf(fp, NULL, _IOLBF, BUFSIZ);
-#endif
-
   g_string_set_size (gs, 0);
   char buf[BUFSIZ];
   while (fgets (buf, sizeof (buf), fp)) {
@@ -846,12 +840,6 @@ output_options_t::get_file_handle (void)
     fail (false, "Cannot open output file `%s': %s",
 	  g_filename_display_name (output_file), strerror (errno));
 
-#ifdef HAVE_SETLINEBUF
-  setlinebuf (fp);
-#else
-  setvbuf(fp, NULL, _IOLBF, BUFSIZ);
-#endif
-
   return fp;
 }