Don't override previously installed signal handlers.

[gnulib.git] / lib / freadable.c

diff --git a/lib/freadable.c b/lib/freadable.c
index 9e9cb09..54703da 100644 (file)
--- a/lib/freadable.c
+++ b/lib/freadable.c
@@ -19,20 +19,21 @@
 /* Specification.  */
 #include "freadable.h"
 
+#include "stdio-impl.h"
+
 bool
 freadable (FILE *fp)
 {
   /* Most systems provide FILE as a struct and the necessary bitmask in
      <stdio.h>, because they need it for implementing getc() and putc() as
      fast macros.  */
-#if defined _IO_ferror_unlocked     /* GNU libc, BeOS */
+#if defined _IO_ferror_unlocked || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Linux libc5 */
   return (fp->_flags & _IO_NO_READS) == 0;
-#elif defined __sferror             /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
-  return (fp->_flags & (__SRW | __SRD)) != 0;
+#elif defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */
+  return (fp_->_flags & (__SRW | __SRD)) != 0;
+#elif defined __EMX__               /* emx+gcc */
+  return (fp->_flags & (_IORW | _IOREAD)) != 0;
 #elif defined _IOERR                /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
-# if defined _SCO_DS                /* OpenServer */
-#  define _flag __flag
-# endif
   return (fp->_flag & (_IORW | _IOREAD)) != 0;
 #elif defined __QNX__               /* QNX */
   return (fp->_Mode & 0x1 /* _MOPENR */) != 0;