Make symlinks work

example/example.hcl

@@ -7,13 +7,36 @@ job "example" {
       driver = "exec2"
 
       config {
-        command =  "/nix/store/y41s1vcn0irn9ahn9wh62yx2cygs7qjj-coreutils-8.32/bin/cat"
-        args = ["/host-etc/nscd.conf"]
-        bind_read_only = {
+        command = "/sw/bin/nix"
+        args = [
+          "--extra-experimental-features", "flakes",
+          "--extra-experimental-features", "nix-command",
+          "run",
+          "github:NixOS/nixpkgs#hello"
+          ]
+        bind = {
           "/nix" = "/nix",
-          "/etc" = "/host-etc",
+        }
+        bind_read_only = {
+          "/etc" = "/etc",
+          "/home/lx/.nix-profile" = "/sw",
         }
       }
+      user = "lx"
+    }
+
+    task "test" {
+      driver = "exec2"
+
+      config {
+        command =  "/nix/store/30j23057fqnnc1p4jqmq73p0gxgn0frq-bash-5.1-p16/bin/sh"
+        args = ["-c", "/nix/store/y41s1vcn0irn9ahn9wh62yx2cygs7qjj-coreutils-8.32/bin/ls /*; /nix/store/y41s1vcn0irn9ahn9wh62yx2cygs7qjj-coreutils-8.32/bin/id"]
+        bind_read_only = {
+          "/etc" = "/etc",
+          "/nix" = "/nix",
+        }
+      }
+      user = "lx"
     }
   }
 }

exec2/driver.go

@@ -434,7 +434,7 @@ func (d *Driver) StartTask(cfg *drivers.TaskConfig) (*drivers.TaskHandle, *drive
 
 	user := cfg.User
 	if user == "" {
-		user = "nobody"
+		user = "0"
 	}
 
 	if cfg.DNS != nil {

executor/executor_linux.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/fs"
 	"os"
 	"os/exec"
 	"path"
@@ -913,7 +914,7 @@ func filepathIsRegular(path string) error {
 	if err != nil {
 		return err
 	}
-	if !f.Mode().Type().IsRegular() {
+	if !(f.Mode().Type().IsRegular() || f.Mode().Type() & fs.ModeType == fs.ModeSymlink) {
 		return fmt.Errorf("path was not a regular file")
 	}
 	return nil