Function trace

pub fn trace<F: FnMut(&Frame) -> bool>(cb: F)

Inspects the current call-stack, passing all active frames into the closure provided to calculate a stack trace.

This function is the workhorse of this library in calculating the stack traces for a program. The given closure cb is yielded instances of a Frame which represent information about that call frame on the stack. The closure is yielded frames in a top-down fashion (most recently called functions first).

The closure’s return value is an indication of whether the backtrace should continue. A return value of false will terminate the backtrace and return immediately.

Once a Frame is acquired you will likely want to call backtrace::resolve to convert the ip (instruction pointer) or symbol address to a Symbol through which the name and/or filename/line number can be learned.

Note that this is a relatively low-level function and if you’d like to, for example, capture a backtrace to be inspected later, then the Backtrace type may be more appropriate.

Required features

This function requires the std feature of the backtrace crate to be enabled, and the std feature is enabled by default.

Panics

This function strives to never panic, but if the cb provided panics then some platforms will force a double panic to abort the process. Some platforms use a C library which internally uses callbacks which cannot be unwound through, so panicking from cb may trigger a process abort.

Example

extern crate backtrace;

fn main() {
    backtrace::trace(|frame| {
        // ...

        true // continue the backtrace
    });
}