introduce logging for debug purposes

xenclient/examples/boot.rs

@@ -8,6 +8,8 @@ use xenclient::elfloader::ElfImageLoader;
 use xenclient::XenClientError;
 
 fn main() -> Result<(), XenClientError> {
+    env_logger::init();
+
     let args: Vec<String> = env::args().collect();
     if args.len() != 2 {
         println!("usage: boot <kernel-image>");

xenclient/examples/simple.rs

@@ -2,6 +2,8 @@ use xenclient::create::{DomainConfig, PvDomainConfig};
 use xenclient::{XenClient, XenClientError};
 
 fn main() -> Result<(), XenClientError> {
+    env_logger::init();
+
     let mut client = XenClient::open()?;
     let mut config = DomainConfig::new();
     config.configure_cpus(1);