diff --git a/update.sh b/update.sh
index 4b82387..bff5328 100755
--- a/update.sh
+++ b/update.sh
@@ -14,6 +14,16 @@ update_file() {
     fi
 }
 
+update_file_sudo() {
+    local A="$1"
+    local B="$2"
+
+    if [ -f "$A" ] && [ -f "$B" ] && [ "$(cat "$A")" != "$(cat "$B")" ]; then
+        sudo cp "$A" "$B"
+        echo "File $B has been updated."
+    fi
+}
+
 update_authorized_keys() {
     [ ! -f ~/.ssh/authorized_keys ] && return
 
@@ -40,3 +50,8 @@ update_file $scriptdir/files/zsh/80-proxy.zsh           ~/.oh-my-zsh/custom/80-p
 update_file $scriptdir/files/zsh/90-other.zsh           ~/.oh-my-zsh/custom/90-other.zsh
 update_file $scriptdir/files/zsh/ys-simple.zsh-theme    ~/.oh-my-zsh/custom/themes/ys-simple.zsh-theme
 update_authorized_keys
+
+sudo_id=$(sudo id -u 2>/dev/null)
+if [ $? -eq 0 ] && [ "$sudo_id" -eq 0 ]; then
+    update_file_sudo $scriptdir/files/proxychains4.conf /etc/proxychains4.conf
+fi