2 files changed, 22 insertions, 12 deletions
diff --git a/src/main.rs b/src/main.rs
index 893b9f5..0694aa5 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,7 +2,8 @@ mod trace;
 
 use crate::trace::{exec, trace};
 use clap::Parser;
-use std::process::Command;
+use fork::{fork, Fork};
+use nix::unistd::Pid;
 
 #[derive(Parser)]
 #[command(author, version, about, long_about = None)]
@@ -12,15 +13,13 @@ struct Args {
 
 fn main() -> anyhow::Result<()> {
     let args = Args::parse();
-    let params = args.command.split(' ').collect::<Vec<&str>>();
 
-    let mut command = Command::new(params[0]);
-    if params.len() > 1 {
-        for arg in &params[1..] {
-            command.arg(arg);
-        }
-    }
-    let pid = exec(&mut command)?;
+    let pid = match fork() {
+        Ok(Fork::Child) => return exec(&args.command),
+        Ok(Fork::Parent(child)) => Pid::from_raw(child as i32),
+        Err(err) => panic!("fork() failed: {err}"),
+    };
+
     trace(pid)?;
 
     Ok(())
diff --git a/src/trace.rs b/src/trace.rs
index 0031fcd..b00b9f9 100644
--- a/src/trace.rs
+++ b/src/trace.rs
@@ -8,16 +8,27 @@ use nix::{
 };
 use std::{os::unix::process::CommandExt, process::Command};
 
-pub fn exec(command: &mut Command) -> anyhow::Result<Pid> {
+pub fn exec(command: &String) -> anyhow::Result<()> {
+    let params: Vec<&str> = command.split(' ').collect();
+
+    let mut command = Command::new(params[0]);
+    command.args(params[1..].iter());
+
     unsafe {
         command.pre_exec(|| ptrace::traceme().map_err(|e| e.into()));
     }
-    let child = command.spawn()?;
-    Ok(Pid::from_raw(child.id() as i32))
+
+    command.exec();
+
+    Ok(())
 }
 
 pub fn trace(pid: Pid) -> anyhow::Result<()> {
     let mut have_to_print = true;
+
+    // First wait if for the parent process
+    _ = waitpid(pid, None)?;
+
     loop {
         have_to_print ^= true;
         ptrace::syscall(pid, None)?;