strace is a diagnostic, debugging and instructional userspace utility with a traditional command-line interface for Linux. It is used to monitor and tamper with interactions between processes and the Linux kernel, which include system calls, signal deliveries, and changes of process state. The operation of strace is made possible by the kernel feature known as ptrace.

strace is one of the longest running free software projects and started even before Linux started.

strace is an important tool for debugging and tracing deployed on most Linux distributions with a small community of active contributors.