1 files changed, 2 insertions, 0 deletions

diff --git a/src/s/sco5.h b/src/s/sco5.h
index 6835c64c641..7d2336b8a94 100644
--- a/src/s/sco5.h
+++ b/src/s/sco5.h
@@ -127,6 +127,8 @@ Boston, MA 02111-1307, USA.  */
 /* SCO Unix has Posix signals, but in 3.2.5 something broken that causes
  * all keyboard-quit signals to be lost after the first one. */
 #undef POSIX_SIGNALS
+
+#define SIGMASKTYPE long
 extern SIGMASKTYPE sigprocmask_set;
 #define sigblock(sig)                                   \
      (sigprocmask_set = SIGEMPTYMASK | (sig),           \