diff --git a/t/1000-mmime.t b/t/1000-mmime.t
index a8be968..448fa5e 100755
--- a/t/1000-mmime.t
+++ b/t/1000-mmime.t
@@ -12,6 +12,6 @@ EOF
 # https://github.com/chneukirchen/mblaze/issues/20
 
 check 'mime -r runs' 'mmime -r <tmp >tmp2'
-check 'no overlong lines' '[ $(wc -L <tmp2) -lt 80 ]'
+check 'no overlong lines' 'awk "{if(length(\$0)>=80)exit 1}" <tmp2'
 check 'no QP when unecessary' ! grep -qF "=?" tmp2
 check 'no further mime necessary' 'mmime -c <tmp2'