Added a basic check to make sure we don't try to transcode a partially written file

src/util/io.rs

@@ -0,0 +1,16 @@
+use std::process;
+
+// checks whether a file is currently open in another program (e.g. still being written)
+pub fn is_file_locked(filepath: &str) -> bool {
+  let cmd = process::Command::new("/usr/bin/lsof")
+    .arg(filepath)
+    .output()
+    .expect("Failed to execute command");
+
+  let results = &String::from_utf8_lossy(&cmd.stdout);
+  if results.contains(filepath) {
+    return true;
+  }
+
+  return false;
+}

src/util/mod.rs

@@ -0,0 +1 @@
+pub mod io;