catchsegv

catchsegv program [arguments]

program
    The executable file you want to run and monitor for segmentation faults.

[arguments]
    Optional arguments that are passed to the program.

catchsegv is a helper program designed to execute another program and intercept segmentation faults (SIGSEGV signals). When a segmentation fault occurs, catchsegv generates a stack trace, which can be invaluable for debugging. This stack trace helps developers pinpoint the location in the code where the memory access violation occurred. It works by setting up a signal handler for SIGSEGV and using tools like addr2line to resolve addresses in the stack trace to source code locations.

catchsegv is particularly useful when debugging programs that don't produce core dumps, or when dealing with complex software where the source of a segmentation fault is difficult to isolate. It's frequently used in conjunction with tools like gdb (GNU Debugger) to provide a more detailed analysis of the program's state at the time of the crash.

catchsegv relies on the presence of debugging information in the executable. If the program was compiled without debugging symbols (e.g., using the -g flag with gcc), the stack trace will contain addresses instead of function names and line numbers, making it much harder to interpret. Also, it only catches SIGSEGV signals. If a program crashes due to another signal it won't be caught.

The stack trace generated by catchsegv usually includes a series of addresses representing the call stack at the point of the segmentation fault. Each address corresponds to a function call in the program. Using tools like addr2line, these addresses can be mapped back to specific source code files and line numbers, assuming debugging information is present. The format of the stack trace may vary slightly depending on the system's architecture and the version of glibc.

catchsegv is particularly helpful when debugging programs that crash intermittently or under specific conditions that are difficult to reproduce in a debugger. It's also useful for quickly obtaining a stack trace in production environments where attaching a full-fledged debugger might not be feasible. It can be used for programs that crash often, even with a debugger attached, to automatically gather the crash information.

catchsegv has been part of the glibc (GNU C Library) project for a long time, providing a convenient mechanism for trapping and reporting segmentation faults. It was designed to aid debugging, especially in situations where standard debugging tools like gdb are not readily available or when analyzing complex program crashes. Its usage has remained relatively consistent over the years, primarily as a wrapper around program execution to catch SIGSEGV.

gdb(1), addr2line(1), strace(1)