Do not attempt to outguess system headers by (re)defining errno.

Recent glibc define error as a cpp macro expanding to a function
call.  Thus, "extern int errno" should cause a link-time undefined
symbol when errno.h is not included.  Here it is, and gcc complains
with the following cryptic warning:

../../gnushogi/sysdeps.c: In function 'ElapsedTime_FIONREAD':
../../gnushogi/sysdeps.c:97: warning: function declaration isn't a prototype

diff --git a/gnushogi/sysdeps.c b/gnushogi/sysdeps.c
index c1e43cf..a8f8bd4 100644 (file)
--- a/gnushogi/sysdeps.c
+++ b/gnushogi/sysdeps.c
@@ -91,7 +91,6 @@ ElapsedTime_FIONREAD(ElapsedTime_mode iop)
     int  nchar;
 
     struct timeval tv;
-    extern int errno;
 
     if ((i = ioctl((int) 0, FIONREAD, &nchar)))
     {
@@ -227,9 +226,6 @@ ElapsedTime_FIONREAD(ElapsedTime_mode iop)
     int  nchar;
     int  i;
 
-    extern int errno;
-
-
     if ((i = ioctl((int) 0, FIONREAD, &nchar)))
     {
         perror("FIONREAD");