tweak result type

Cargo.lock

@@ -1,5 +1,7 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 3
+
 [[package]]
 name = "aho-corasick"
 version = "0.7.18"
@@ -141,6 +143,7 @@ dependencies = [
  "libloading",
  "libretro-sys",
  "num_enum",
+ "once_cell",
 ]
 
 [[package]]
@@ -154,6 +157,7 @@ dependencies = [
  "libloading",
  "num_enum",
  "sdl2",
+ "tempfile",
 ]
 
 [[package]]
@@ -341,6 +345,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "once_cell"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "692fcb63b64b1758029e0a96ee63e049ce8c5948587f2f7208df04625e5f6b56"
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.14"
@@ -562,6 +572,15 @@ dependencies = [
  "rand_core 0.3.1",
 ]
 
+[[package]]
+name = "redox_syscall"
+version = "0.2.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8383f39639269cde97d255a32bdb68c047337295414940c68bdd30c2e13203ff"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "regex"
 version = "1.5.4"
@@ -579,6 +598,15 @@ version = "0.6.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f497285884f3fcff424ffc933e56d7cbca511def0c9831a7f9b5f6153e3cc89b"
 
+[[package]]
+name = "remove_dir_all"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3acd125665422973a33ac9d3dd2df85edad0f4ae9b00dafb1a05e43a9f5ef8e7"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "sdl2"
 version = "0.32.2"
@@ -651,6 +679,20 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "tempfile"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dac1c663cfc93810f88aed9b8941d48cabf856a1b111c29a40439018d870eb22"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "rand 0.8.4",
+ "redox_syscall",
+ "remove_dir_all",
+ "winapi",
+]
+
 [[package]]
 name = "textwrap"
 version = "0.11.0"

src/main.rs

@@ -31,7 +31,7 @@ use ferretro_components::provided::{
 
 use crate::gui::*;
 
-pub type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;
+pub type Result<T> = std::result::Result<T, Box<dyn std::error::Error + Send + Sync>>;
 
 mod gui;