diff --git a/contrib/completion/git-completion.tcsh b/contrib/completion/git-completion.tcsh
index 6104a42a23..4a790d8f4e 100644
--- a/contrib/completion/git-completion.tcsh
+++ b/contrib/completion/git-completion.tcsh
@@ -41,7 +41,7 @@ if ( ! -e ${__git_tcsh_completion_original_script} ) then
 	exit
 endif
 
-cat << EOF > ${__git_tcsh_completion_script}
+cat << EOF >! ${__git_tcsh_completion_script}
 #!bash
 #
 # This script is GENERATED and will be overwritten automatically.