bashreadline-bpfcc8

Usage

Overview

bashreadline traces the return of the readline() function using uprobes, to show the bash commands that were entered interactively, system wide. The entered command may fail: this is just showing what was entered.

This program is also a basic example of eBPF/bcc and uprobes.

This makes use of a Linux 4.4 feature (bpf_perf_event_output()); for kernels older than 4.4, see the version under tools/old, which uses an older mechanism

Since this uses BPF, only the root user can use this tool.

Requirements

CONFIG_BPF and bcc.

Options

-h

Print usage message.

-s

Specify the location of libreadline.so shared library when you failed to run the script directly with error: "Exception: could not determine address of symbol ´readline´". Default value is /lib/libreadline.so.

Examples

Trace bash commands system wide:

# bashreadline

Fields

TIME

Time of the command (HH:MM:SS).

PID

Process ID of the bash shell.

COMMAND

Entered command.

Overhead

As the rate of interactive bash commands is expected to be very low (<<100/s), the overhead of this program is expected to be negligible.

Source

This is from bcc.

https://github.com/iovisor/bcc

Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.

OS

Linux

Stability

Unstable - in development.