EACCES permission denied on /tmp/claude/* on Android/Termux

Description

Claude Code fails with EACCES: permission denied, mkdir '/tmp/claude/...' errors on Android/Termux when running commands that take more than a few seconds. The commands execute successfully, but Claude Code's internal task tracking fails because it tries to create directories in /tmp/claude/ which is inaccessible on Android.

Environment

• Claude Code version: 2.1.3
• Node version: v25.2.1
• Platform: Android 14 (Termux)
• Shell: bash

Error Message

EACCES: permission denied, mkdir '/tmp/claude/-storage-emulated-0-ai-projects-nas-admin/tasks'

Root Cause

1. Claude Code hardcodes /tmp/claude/... for internal task tracking
2. On Android, /tmp is a system directory that apps cannot access
3. Termux uses $TMPDIR (typically /data/data/com.termux/files/usr/tmp) instead of /tmp
4. Claude Code does not respect $TMPDIR or $PREFIX/tmp

Reproduction Steps

1. Install Claude Code on Termux (Android)
2. Run any command that takes more than 2-3 seconds (e.g., SSH commands, API calls)
3. Observe the EACCES error

Expected Behavior

Claude Code should use the platform-appropriate temp directory:

• Check $TMPDIR first (set by Termux)
• Fall back to $PREFIX/tmp on Termux
• Only use /tmp as last resort on systems where it's accessible

Current Workaround

Run commands in the background and check results separately:

long_command > output.txt &
sleep 2
cat output.txt

Notes

• The actual commands execute successfully - only the task tracking fails
• This issue has been occurring since at least December 2025
• Affects all Claude Code sessions on Termux