ptype

Overview ¶

Command ptype prints Go types from a binary using DWARF info.

ptype binary <types...> prints types matching the given regexps in binary in (approximate) Go syntax. If no types are named, ptype prints all named types.

The printed types are annotated with information about sizes, field offsets, and gaps between fields.

The printed types are as close as possible to Go type syntax, but aren't guaranteed to be legal Go code (e.g., unions have no Go equivalent). ptype backs out high-level Go types such as maps and channels where possible.

For example, ptype ptype runtime.mcache prints:

type runtime.mcache struct {
        // 1200 byte struct
        next_sample int32                         // offset 0
        // 4 byte gap
        local_scan uintptr                        // offset 8
        tiny uintptr                              // offset 16
        tinyoffset uintptr                        // offset 24
        local_tinyallocs uintptr                  // offset 32
        alloc [67]*mspan                          // offset 40
        stackcache [4]struct {                    // offset 576
                list runtime.gclinkptr            // offset 576 + 16*i
                size uintptr                      // offset 576 + 16*i + 8
        }
        local_nlookup uintptr                     // offset 640
        local_largefree uintptr                   // offset 648
        local_nlargefree uintptr                  // offset 656
        local_nsmallfree [67]uintptr              // offset 664
}