diff --git a/src/fop.rs b/src/fop.rs
index 4f80bd6..c9a767e 100644
--- a/src/fop.rs
+++ b/src/fop.rs
@@ -18,7 +18,7 @@
 
 use std::{
 	env::args,
-	io::{ Read, stdin, Write },
+	io::{ Read, stdin, stdout, Write },
 	process::{ Command, exit, Stdio },
 };
 
@@ -26,7 +26,7 @@ extern crate sysexits;
 extern crate getopt;
 
 use getopt::{ Opt, Parser };
-use sysexits::{ EX_DATAERR, EX_USAGE };
+use sysexits::{ EX_DATAERR, EX_IOERR, EX_UNAVAILABLE, EX_USAGE };
 
 fn main() {
 	let argv = args().collect::<Vec<String>>();
@@ -54,43 +54,65 @@ fn main() {
 		exit(EX_USAGE);
 	});
 
-	let index = argv[index_arg].parse::<usize>().unwrap_or_else(|_| {
-		eprintln!("{}: {}: Not an integer.", argv[0], argv[1]);
+	let index = argv[index_arg].parse::<usize>().unwrap_or_else(|e| {
+		eprintln!("{}: {}: {}.", argv[0], argv[1], e);
 		exit(EX_DATAERR);
 	});
 
 	let mut buf = String::new();
-	stdin().read_to_string(&mut buf).unwrap();
+	let _ = stdin().read_to_string(&mut buf);
 	let mut fields = buf.split(d).collect::<Vec<&str>>();
 
-	let opts = argv.iter().clone().skip(command_arg + 1).collect::<Vec<&String>>();
+	let opts = argv
+		.iter()
+		.clone()
+		.skip(command_arg + 1)
+		.collect::<Vec<&String>>();
 
 	let mut spawned = Command::new(argv.get(command_arg).unwrap())
 		.args(opts)
 		.stdin(Stdio::piped())
 		.stdout(Stdio::piped())
 		.spawn()
-		.unwrap();
+		.unwrap_or_else( |e| {
+			eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
+			exit(EX_UNAVAILABLE);
+		});
 
 	let field = fields.get(index).unwrap_or_else(|| {
 		eprintln!(
 			"{}: {}: No such index in input.",
 			argv[0],
-			index.to_string()
+			index.to_string(),
 		);
 		exit(EX_DATAERR);
 	});
 
 	if let Some(mut child_stdin) = spawned.stdin.take() {
-		child_stdin.write_all(field.as_bytes()).unwrap();
+		let _ = child_stdin.write_all(field.as_bytes());
 		drop(child_stdin);
 	}
 
-	let output = spawned.wait_with_output().unwrap();
+	let output = spawned.wait_with_output().unwrap_or_else(|e| {
+		eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
+		exit(EX_IOERR);
+	});
 
-	let new_field = String::from_utf8(output.stdout).unwrap();
+	let mut replace = output.stdout.clone();
+
+	if replace.pop() != Some(b'\n') { replace = output.stdout; }
+
+	let new_field = String::from_utf8(replace).unwrap_or_else(|e| {
+		eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
+		exit(EX_IOERR);
+	});
 
 	fields[index] = &new_field;
 
-	print!("{}", fields.join(&d.to_string()));
+	stdout().write_all(
+		fields.join(&d.to_string()).as_bytes()
+	).unwrap_or_else(|e|{
+		eprintln!("{}: {}.", argv[0], e);
+		exit(EX_IOERR);
+	});
 }