fixed permission checking on commands, added "which" command.

cmd/which.go

@@ -0,0 +1,30 @@
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+var ErrNotFound = errors.New("which: command not found")
+
+func Which(cmd string) (string, error) {
+
+	command := exec.Command("which", cmd)
+
+	outputBytes, err := command.Output()
+	if err != nil {
+		var exitErr *exec.ExitError
+		if errors.As(err, &exitErr) {
+			if exitErr.ExitCode() == 1 {
+				return "", ErrNotFound
+			} else {
+				return "", fmt.Errorf("command error: %w", err)
+			}
+		}
+	}
+
+	return strings.Trim(string(outputBytes), "\n"), nil
+
+}

linux/utils.go

@@ -3,6 +3,7 @@ package linux
 import (
 	"errors"
 	"fmt"
+	cmd2 "git.shadowhosting.xyz/Eggactyl/shell/cmd"
 	"golang.org/x/sys/unix"
 	"io/fs"
 	"os"
@@ -11,9 +12,20 @@ import (
 
 func (cmd *LinuxCommand) isCommandExecutable(command string) (bool, error) {
 
+	whichOut, err := cmd2.Which(command)
+	if err != nil {
+		if errors.Is(err, cmd2.ErrNotFound) {
 			if _, err := os.Stat(command); errors.Is(err, fs.ErrNotExist) {
 				return false, err
 			}
+		} else {
+			return false, err
+		}
+	}
+
+	if len(whichOut) > 0 {
+		command = whichOut
+	}
 
 	if err := unix.Access(command, unix.X_OK); err != nil {
 		if err == unix.EACCES {