1 files changed, 1 insertions, 1 deletions

diff --git a/src/plugins/man_extractor.c b/src/plugins/man_extractor.c
index 15835ec..90a0631 100644
--- a/src/plugins/man_extractor.c
+++ b/src/plugins/man_extractor.c
@@ -116,7 +116,7 @@ EXTRACTOR_man_extract (const char *buf,
                          &buf[pos],
                          xlen)) || ((pos != 0) && (buf[pos - 1] != '\n'))))
     {
-      if (!isgraph (buf[pos]) && !isspace (buf[pos]))
+      if (!isgraph (buf[pos]) && !isspace ((unsigned char) buf[pos]))
         return 0;
       pos++;
     }