From 3ea33a06165018a83d6838e36eea938c55e4ccdf Mon Sep 17 00:00:00 2001
From: Josh McKinney <joshka@openai.com>
Date: Fri, 21 Nov 2025 14:17:40 -0800
Subject: [PATCH] fix(tui): Fail when stdin is not a terminal (#6382)
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Piping to codex fails to do anything useful and locks up the process.
We currently check for stdout, but not stdin

```
❯ echo foo|just c
cargo run --bin codex -- "$@"
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.21s
     Running `target/debug/codex`
Error: stdin is not a terminal
error: Recipe `codex` failed on line 10 with exit code 1
```
---
 codex-rs/tui/src/tui.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/codex-rs/tui/src/tui.rs b/codex-rs/tui/src/tui.rs
index d758996d2..7cbf252e7 100644
--- a/codex-rs/tui/src/tui.rs
+++ b/codex-rs/tui/src/tui.rs
@@ -2,6 +2,7 @@ use std::fmt;
 use std::io::IsTerminal;
 use std::io::Result;
 use std::io::Stdout;
+use std::io::stdin;
 use std::io::stdout;
 use std::panic;
 use std::pin::Pin;
@@ -127,6 +128,9 @@ pub fn restore() -> Result<()> {
 
 /// Initialize the terminal (inline viewport; history stays in normal scrollback)
 pub fn init() -> Result<Terminal> {
+    if !stdin().is_terminal() {
+        return Err(std::io::Error::other("stdin is not a terminal"));
+    }
     if !stdout().is_terminal() {
         return Err(std::io::Error::other("stdout is not a terminal"));
     }