[3/3] nfsref: "nfsref SUBCOMMAND -?" should display useful information

diff --git a/src/nfsref/add.c b/src/nfsref/add.c
index e0e347f..ce7f813 100644
--- a/src/nfsref/add.c
+++ b/src/nfsref/add.c
@@ -39,6 +39,7 @@ 
 #include "junction.h"
 #include "nsdb.h"
 #include "xlog.h"
+#include "gpl-boiler.h"
 #include "nfsref.h"
 
 /**
@@ -47,6 +48,39 @@ 
 #define FSN_DEFAULT_TTL		(300)
 
 /**
+ * Display help message for "add" subcommand
+ *
+ * @param progname NUL-terminated C string containing name of program
+ * @return program exit status
+ */
+int
+nfsref_add_help(const char *progname)
+{
+	fprintf(stderr, " \n");
+
+	fprintf(stderr, "Usage: %s [ -t type ] add <junction path> "
+			"<server> <export> [ <server> <export> ... ]\n\n",
+		progname);
+
+	fprintf(stderr, "Add a new junction containing the specified list "
+			"of fileset locations.\n");
+	fprintf(stderr, "<junction path> is the filename of the new junction.  "
+			"<server> is the hostname\n");
+	fprintf(stderr, "or IP address of an NFS server where the fileset is "
+			"located.  <export> is the\n");
+	fprintf(stderr, "export pathname of the fileset on that server.\n\n");
+
+	fprintf(stderr, "For NFS basic junctions, the location list is stored "
+			"locally in the junction.\n");
+	fprintf(stderr, "For FedFS junctions, the location list is stored "
+			"as new FSN and FSL records\n");
+	fprintf(stderr, "on an NSDB.\n");
+
+	fprintf(stderr, "%s", fedfs_gpl_boilerplate);
+	return EXIT_SUCCESS;
+}
+
+/**
  * Fill in default settings for NFSv4.0 fs_locations4
  *
  * @param new NFS location structure to fill in
diff --git a/src/nfsref/lookup.c b/src/nfsref/lookup.c
index ef4a87d..96454fd 100644
--- a/src/nfsref/lookup.c
+++ b/src/nfsref/lookup.c
@@ -32,9 +32,35 @@ 
 #include "junction.h"
 #include "nsdb.h"
 #include "xlog.h"
+#include "gpl-boiler.h"
 #include "nfsref.h"
 
 /**
+ * Display help message for "lookup" subcommand
+ *
+ * @param progname NUL-terminated C string containing name of program
+ * @return program exit status
+ */
+int
+nfsref_lookup_help(const char *progname)
+{
+	fprintf(stderr, " \n");
+
+	fprintf(stderr, "Usage: %s [ -t type ] lookup <junction path>\n\n",
+		progname);
+
+	fprintf(stderr, "Display the contents of the junction at "
+			"<junction path>.  For NFS basic\n");
+	fprintf(stderr, "junctions, the local contents of the junction "
+			"are displayed.  For FedFS\n");
+	fprintf(stderr, "junctions, FSL records are retrieved from the "
+			"NSDB and displayed.\n");
+
+	fprintf(stderr, "%s", fedfs_gpl_boilerplate);
+	return EXIT_SUCCESS;
+}
+
+/**
  * Convert a boolean value into a displayable string constant
  *
  * @param value boolean value
diff --git a/src/nfsref/nfsref.c b/src/nfsref/nfsref.c
index be05bda..ef7c5a7 100644
--- a/src/nfsref/nfsref.c
+++ b/src/nfsref/nfsref.c
@@ -97,6 +97,7 @@  main(int argc, char **argv)
 	char *progname, *subcommand, *junct_path;
 	enum nfsref_type type;
 	int arg, exit_status;
+	_Bool help;
 
 	(void)umask(S_IWGRP | S_IWOTH);
 
@@ -124,6 +125,7 @@  main(int argc, char **argv)
 		goto out;
 	}
 
+	help = false;
 	type = NFSREF_TYPE_UNSPECIFIED;
 	while ((arg = getopt_long(argc, argv, nfsref_opts,
 			nfsref_longopts, NULL)) != -1) {
@@ -144,17 +146,16 @@  main(int argc, char **argv)
 			}
 			break;
 		case '?':
-			nfsref_usage(progname);
-			exit(EXIT_SUCCESS);
+			help = true;
 		}
 	}
-	if (argc < optind + 2) {
-		fprintf(stderr, "Not enough positional parameters\n");
+
+	if (argc < optind + 1) {
 		nfsref_usage(progname);
 		goto out;
 	}
 
-	if (geteuid() != 0) {
+	if (!help && geteuid() != 0) {
 		fprintf(stderr, "Root permission is required\n");
 		goto out;
 	}
@@ -163,6 +164,10 @@  main(int argc, char **argv)
 	junct_path = argv[optind + 1];
 
 	if (strcasecmp(subcommand, "add") == 0) {
+		if (help) {
+			exit_status = nfsref_add_help(progname);
+			goto out;
+		}
 		if (argc < optind + 3) {
 			fprintf(stderr, "Not enough positional parameters\n");
 			nfsref_usage(progname);
@@ -172,12 +177,20 @@  main(int argc, char **argv)
 		if (exit_status == EXIT_SUCCESS)
 			(void)junction_flush_exports_cache();
 	} else if (strcasecmp(subcommand, "remove") == 0) {
+		if (help) {
+			exit_status = nfsref_remove_help(progname);
+			goto out;
+		}
 		exit_status = nfsref_remove(type, junct_path);
 		if (exit_status == EXIT_SUCCESS)
 			(void)junction_flush_exports_cache();
-	} else if (strcasecmp(subcommand, "lookup") == 0)
+	} else if (strcasecmp(subcommand, "lookup") == 0) {
+		if (help) {
+			exit_status = nfsref_lookup_help(progname);
+			goto out;
+		}
 		exit_status = nfsref_lookup(type, junct_path);
-	else {
+	} else {
 		xlog(L_ERROR, "Unrecognized subcommand: %s", subcommand);
 		nfsref_usage(progname);
 	}
diff --git a/src/nfsref/nfsref.h b/src/nfsref/nfsref.h
index 8e40fd9..e9dd9ae 100644
--- a/src/nfsref/nfsref.h
+++ b/src/nfsref/nfsref.h
@@ -40,4 +40,8 @@  int	 nfsref_add(enum nfsref_type type, const char *junct_path, char **argv,
 int	 nfsref_remove(enum nfsref_type type, const char *junct_path);
 int	 nfsref_lookup(enum nfsref_type type, const char *junct_path);
 
+int	 nfsref_add_help(const char *progname);
+int	 nfsref_remove_help(const char *progname);
+int	 nfsref_lookup_help(const char *progname);
+
 #endif	/* !FEDFS_NFSREF_H */
diff --git a/src/nfsref/remove.c b/src/nfsref/remove.c
index 7dd5997..7bee9de 100644
--- a/src/nfsref/remove.c
+++ b/src/nfsref/remove.c
@@ -34,9 +34,32 @@ 
 #include "fedfs.h"
 #include "junction.h"
 #include "xlog.h"
+#include "gpl-boiler.h"
 #include "nfsref.h"
 
 /**
+ * Display help message for "remove" subcommand
+ *
+ * @param progname NUL-terminated C string containing name of program
+ * @return program exit status
+ */
+int
+nfsref_remove_help(const char *progname)
+{
+	fprintf(stderr, " \n");
+
+	fprintf(stderr, "Usage: %s [ -t type ] remove <junction path>\n\n",
+		progname);
+
+	fprintf(stderr, "Remove the junction at <junction path>.  For FedFS "
+			"junctions, FSL and FSN\n");
+	fprintf(stderr, "records are removed from the NSDB.\n");
+
+	fprintf(stderr, "%s", fedfs_gpl_boilerplate);
+	return EXIT_SUCCESS;
+}
+
+/**
  * Remove any NFS junction information
  *
  *