Allow running fping --help even when raw socket can't be opened, fixes #131

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e164a0e9c7059e526c13d85b68601a418af07373..7641dacc0dcc2fd20492486e5769ba111877f386 100644 (file)
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ fping 4.1 (UNRELEASED)
 
 - Fix problem when socket fd is 0 (#125, thanks Ramón Novoa!)
 - Fix running on servers with disabled IPv6 (#118, thanks Simon Matter)
+- Allow running "fping -h" or "--help" even when raw socket can't be opened (#131, thanks @teto)
 
 fping 4.0 (2017-04-23)
 ======================

diff --git a/src/fping.c b/src/fping.c
index 401cbda5fbd813445661c6d218ab9a0f2892158c..8b9ce2510f8b2eec5d0b2602e308b8fd58f06961 100644 (file)
--- a/src/fping.c
+++ b/src/fping.c
@@ -352,6 +352,12 @@ int main(int argc, char** argv)
     HOST_ENTRY* cursor;
     struct optparse optparse_state;
 
+    /* pre-parse -h/--help, so that we also can output help information
+     * without trying to open the socket, which might fail */
+    if(argc == 2 && ( strcmp(argv[1],"-h")==0 || strcmp(argv[1],"--help")==0 )) {
+        usage(0);
+    }
+
     socket4 = open_ping_socket_ipv4(ping_data_size);
 #ifdef IPV6
     socket6 = open_ping_socket_ipv6(ping_data_size);