diff --git a/commands.h b/commands.h
index e719c491..01bf387e 100644
--- a/commands.h
+++ b/commands.h
@@ -65,9 +65,6 @@ struct cmd_group {
 	const struct cmd_struct commands[];
 };
 
-/* btrfs.c */
-int prefixcmp(const char *str, const char *prefix);
-
 int handle_command_group(const struct cmd_group *grp, int argc,
 			 char **argv);
 
diff --git a/help.c b/help.c
index b5718049..19b0d357 100644
--- a/help.c
+++ b/help.c
@@ -359,12 +359,3 @@ void help_command_group(const struct cmd_group *grp, int argc, char **argv)
 	usage_command_group(grp, full, 0);
 }
 
-int prefixcmp(const char *str, const char *prefix)
-{
-	for (; ; str++, prefix++)
-		if (!*prefix)
-			return 0;
-		else if (*str != *prefix)
-			return (unsigned char)*prefix - (unsigned char)*str;
-}
-
diff --git a/utils.c b/utils.c
index 5aab60d3..d2489e70 100644
--- a/utils.c
+++ b/utils.c
@@ -2305,6 +2305,15 @@ int string_is_numerical(const char *str)
 	return 1;
 }
 
+int prefixcmp(const char *str, const char *prefix)
+{
+	for (; ; str++, prefix++)
+		if (!*prefix)
+			return 0;
+		else if (*str != *prefix)
+			return (unsigned char)*prefix - (unsigned char)*str;
+}
+
 /* Subvolume helper functions */
 /*
  * test if name is a correct subvolume name
diff --git a/utils.h b/utils.h
index 31ccbf07..24d0a200 100644
--- a/utils.h
+++ b/utils.h
@@ -146,6 +146,7 @@ int btrfs_tree_search2_ioctl_supported(int fd);
 
 unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode);
 int string_is_numerical(const char *str);
+int prefixcmp(const char *str, const char *prefix);
 
 /*
  * Global program state, configurable by command line and available to