Strace is a powerful tool in Linux that can be used to trace system calls, signals, and other related information. It is a valuable tool for system administrators, developers, and programmers to debug issues and optimize system performance. With Strace, you can gain deep insights into how your system is working and identify potential issues.
In this article, we will provide 10 Strace command examples for effective system analysis in Linux.
- Tracing a Command
The simplest use case for Strace is to trace a command. To do this, simply prefix the command with “strace”. For example:
strace ls
This command will show all the system calls made by the “ls” command.
- Tracing a Running Process
To trace a running process, use the “-p” option followed by the process ID. For example:
strace -p 1234
This command will attach Strace to the process with ID 1234 and show all the system calls made by that process.
- Filtering System Calls
To filter the system calls displayed by Strace, use the “-e” option followed by a comma-separated list of system calls. For example:
strace -e open,close ls
This command will only display the “open” and “close” system calls made by the “ls” command.
- Showing System Call Arguments
To display the arguments passed to a system call, use the “-v” option. For example:
strace -v cat file.txt
This command will show the arguments passed to the “read” system call made by the “cat” command when reading from the “file.txt” file.
- Displaying Timestamps
To display timestamps for each system call, use the “-t” option. For example:
strace -t ls
This command will show the time of each system call made by the “ls” command.
- Redirecting Output
By default, Strace outputs to the terminal. To redirect the output to a file, use the “-o” option followed by the filename. For example:
strace -o output.txt ls
This command will redirect the output of the “ls” command to the “output.txt” file.
- Limiting Output
To limit the output displayed by Strace, use the “-c” option. For example:
strace -c ls
This command will display a summary of the system calls made by the “ls” command instead of the full output.
- Tracing Child Processes
To trace child processes created by a command, use the “-f” option. For example:
strace -f ls
This command will trace the “ls” command and any child processes it creates.
- Displaying Signal Information
To display information about signals received by a process, use the “-s” option followed by the signal name or number. For example:
strace -s SIGINT ls
This command will display information about the “SIGINT” signal received by the “ls” command.
- Monitoring System Calls
To monitor all system calls made by the system, use the “-e” option followed by “all”. For example:
strace -e all -o output.txt
This command will monitor all system calls made by the system and output them to the “output.txt” file.
Conclusion
In conclusion, Strace is a valuable tool for system analysis in Linux. With its ability to trace system calls, signals, and other related information, Strace can help you identify potential issues and optimize system performance. The examples provided in this article are just a small subset of what Strace can do. We recommend exploring Strace’s documentation and trying out different options to gain a deeper understanding of your system’s behavior. By mastering the Strace command, you can become more effective at troubleshooting and optimizing your Linux systems.