diff --git a/lib/include/service.h b/lib/include/service.h
index 593b221..eaa35bb 100644
--- a/lib/include/service.h
+++ b/lib/include/service.h
@@ -45,8 +45,8 @@ enum {
 };
 
 typedef struct exec_t {
-	char **argv;
-	char *raw_argv;
+	char **argv;		/* NULL terminated argument vector */
+	char *raw_argv;		/* backing store for argv contents */
 
 	struct exec_t *next;
 } exec_t;
@@ -56,15 +56,20 @@ typedef struct service_t {
 	int target;		/* TGT_* service target */
 	char *name;		/* canonical service name */
 	char *desc;		/* description string */
-	exec_t *exec;		/* command lines to execute */
 	char *ctty;		/* controlling tty or log file */
-
 	int rspwn_limit;	/* maximum respawn count */
 
-	char **before;		/* services that must be executed later */
-	char **after;		/* services that must be executed first */
-	char *raw_after;
-	char *raw_before;
+	/* linked list of command lines to execute */
+	exec_t *exec;
+
+	/* NULL terminated array of services that must be executed later */
+	char **before;
+
+	/* NULL terminated array of services that must be executed first */
+	char **after;
+
+	char *raw_before;	/* backing store for 'before' contents */
+	char *raw_after;	/* backing store for 'after' contents */
 
 	pid_t pid;
 	int status;		/* process exit status */
diff --git a/lib/include/util.h b/lib/include/util.h
index a6e96fa..a9d111b 100644
--- a/lib/include/util.h
+++ b/lib/include/util.h
@@ -73,6 +73,17 @@ char *rdline(int fd, int argc, const char *const *argv);
 */
 int unescape(char *src);
 
+/*
+	Split a space seperated string into a sequence of null-terminated
+	strings. Return a NULL terminated array of strings pointing to the
+	start of each sub string.
+
+	If a double quote is encountered, the entire string up to to the next,
+	unescaped double quite is interpreted as a single sub string and
+	fed through the unescape function.
+
+	The returned array must be freed with free().
+*/
 char **split_argv(char *str);
 
 /*