fix: detect dmenu mode correctly using fstat

Previously, poll() on /dev/null returned "readable" (EOF),
causing dmenu mode to trigger when launched from keybinds.

Now uses fstat() to check if stdin is a pipe or regular file
before checking for data. Character devices (TTY, /dev/null)
no longer trigger dmenu mode.

Fixes items not showing when launched from window manager keybinds.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Cargo.lock

@@ -859,7 +859,7 @@ checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
 
 [[package]]
 name = "owlry"
-version = "0.1.2"
+version = "0.1.4"
 dependencies = [
  "clap",
  "dirs",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "owlry"
-version = "0.1.2"
+version = "0.1.4"
 edition = "2024"
 rust-version = "1.90"
 description = "A lightweight, owl-themed application launcher for Wayland"

src/main.rs

@@ -8,7 +8,7 @@ mod ui;
 
 use app::OwlryApp;
 use cli::CliArgs;
-use log::info;
+use log::{info, warn};
 
 fn main() {
     env_logger::Builder::from_env(env_logger::Env::default().default_filter_or("info")).init();
@@ -17,6 +17,18 @@ fn main() {
 
     info!("Starting Owlry launcher");
 
+    // Diagnostic: log critical environment variables
+    let home = std::env::var("HOME").unwrap_or_else(|_| "<not set>".to_string());
+    let path = std::env::var("PATH").unwrap_or_else(|_| "<not set>".to_string());
+    let xdg_data = std::env::var("XDG_DATA_HOME").unwrap_or_else(|_| "<not set>".to_string());
+    info!("HOME={}", home);
+    info!("PATH={}", path);
+    info!("XDG_DATA_HOME={}", xdg_data);
+
+    if home == "<not set>" || path == "<not set>" {
+        warn!("Critical environment variables missing! Items may not load correctly.");
+    }
+
     let app = OwlryApp::new(args);
     std::process::exit(app.run());
 }

src/providers/dmenu.rs

@@ -17,17 +17,37 @@ impl DmenuProvider {
     }
 
     /// Check if stdin has data (non-blocking check)
+    /// Returns true only if stdin is a pipe or regular file with data available.
+    /// Returns false for TTYs, /dev/null, and other character devices.
     pub fn has_stdin_data() -> bool {
         use std::os::unix::io::AsRawFd;
 
         let stdin_fd = io::stdin().as_raw_fd();
+
+        // First check if stdin is a pipe or regular file (valid dmenu input sources)
+        // Character devices (TTY, /dev/null) should NOT trigger dmenu mode
+        let mut stat_buf: libc::stat = unsafe { std::mem::zeroed() };
+        let stat_result = unsafe { libc::fstat(stdin_fd, &mut stat_buf) };
+        if stat_result != 0 {
+            return false;
+        }
+
+        let mode = stat_buf.st_mode;
+        let is_pipe = (mode & libc::S_IFMT) == libc::S_IFIFO;
+        let is_file = (mode & libc::S_IFMT) == libc::S_IFREG;
+
+        // Only check for data if stdin is a pipe or file
+        if !is_pipe && !is_file {
+            return false;
+        }
+
+        // Non-blocking poll to check if data is available
         let mut poll_fd = libc::pollfd {
             fd: stdin_fd,
             events: libc::POLLIN,
             revents: 0,
         };
 
-        // Non-blocking poll with 0 timeout
         let result = unsafe { libc::poll(&mut poll_fd, 1, 0) };
         result > 0 && (poll_fd.revents & libc::POLLIN) != 0
     }

src/providers/mod.rs

@@ -10,6 +10,7 @@ pub use uuctl::UuctlProvider;
 
 use fuzzy_matcher::FuzzyMatcher;
 use fuzzy_matcher::skim::SkimMatcherV2;
+use log::info;
 
 /// Represents a single searchable/launchable item
 #[derive(Debug, Clone)]
@@ -110,6 +111,11 @@ impl ProviderManager {
     pub fn refresh_all(&mut self) {
         for provider in &mut self.providers {
             provider.refresh();
+            info!(
+                "Provider '{}' loaded {} items",
+                provider.name(),
+                provider.items().len()
+            );
         }
     }