From b7fad288c7d6a6fb73f0ed510fd933454286a150 Mon Sep 17 00:00:00 2001
From: Axel Kohlmeyer <akohlmey@gmail.com>
Date: Tue, 8 Aug 2023 20:30:05 -0400
Subject: [PATCH] fix ability to select a temporary directory (for image files)

---
 tools/lammps-gui/lammpsgui.cpp   |  8 +++++++-
 tools/lammps-gui/preferences.cpp | 11 ++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/tools/lammps-gui/lammpsgui.cpp b/tools/lammps-gui/lammpsgui.cpp
index cf67916e0c..19dcc8b108 100644
--- a/tools/lammps-gui/lammpsgui.cpp
+++ b/tools/lammps-gui/lammpsgui.cpp
@@ -132,7 +132,13 @@ LammpsGui::LammpsGui(QWidget *parent, const char *filename) :
 #else
     if (!tmpdir) tmpdir = "/tmp";
 #endif
-    settings.setValue("tempdir", QString(tmpdir));
+
+    QFileInfo newtmp(settings.value("tempdir", QString(tmpdir)).toString());
+    if (newtmp.isDir() && newtmp.isWritable()) {
+        settings.setValue("tempdir", newtmp.filePath());
+    } else {
+        settings.setValue("tempdir", QString(tmpdir));
+    }
 
     lammps_args.clear();
     lammps_args.push_back(mystrdup("LAMMPS-GUI"));
diff --git a/tools/lammps-gui/preferences.cpp b/tools/lammps-gui/preferences.cpp
index f50a4be2c0..a7ee670694 100644
--- a/tools/lammps-gui/preferences.cpp
+++ b/tools/lammps-gui/preferences.cpp
@@ -98,6 +98,11 @@ void Preferences::accept()
     if (field)
         if (field->hasAcceptableInput()) settings->setValue("nthreads", field->text());
 
+    // store temp dir
+    field = tabWidget->findChild<QLineEdit *>("tmpedit");
+    if (field)
+        if (field->hasAcceptableInput()) settings->setValue("tempdir", field->text());
+
     // store image width, height, and zoom
 
     settings->beginGroup("snapshot");
@@ -248,7 +253,11 @@ void GeneralTab::newtmpfolder()
     QLineEdit *field = findChild<QLineEdit *>("tmpedit");
     QString tmpdir =
         QFileDialog::getExistingDirectory(this, "Find Folder for Temporary Files", field->text());
-    if (!tmpdir.isEmpty()) field->setText(tmpdir);
+
+    if (!tmpdir.isEmpty()) {
+        QFileInfo newtmp(tmpdir);
+        if (newtmp.isDir() && newtmp.isWritable()) field->setText(tmpdir);
+    }
 }
 
 void GeneralTab::pluginpath()