[#absl-GetStackFramesWithContext]
= xref:absl.adoc[absl]::GetStackFramesWithContext
:relfileprefix: ../
:mrdocs:

Records program counter values obtained from a signal handler. Records program counter values for up to `max_depth` frames, skipping the most recent `skip_count` stack frames, stores their corresponding values and sizes in `results` and `sizes` buffers, and returns the number of frames stored. (Note that the frame generated for the `absl::GetStackFramesWithContext()` routine itself is also skipped.)

== Synopsis

Declared in `<absl/debugging/stacktrace.h>`

[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
extern
int
GetStackFramesWithContext(
    void** result,
    int* sizes,
    int max_depth,
    int skip_count,
    void const* uc,
    int* min_dropped_frames);
----

== Description

The `uc` parameter, if non‐null, should be a pointer to a `ucontext_t` value passed to a signal handler registered via the `sa_sigaction` field of a `sigaction` struct. (See http://man7.org/linux/man‐pages/man2/sigaction.2.html.) The `uc` value may help a stack unwinder to provide a better stack trace under certain conditions. `uc` may safely be null.

The `min_dropped_frames` output parameter, if non‐null, points to the location to note any dropped stack frames, if any, due to buffer limitations or other reasons. (This value will be set to `0` if no frames were dropped.) The number of total stack frames is guaranteed to be >= skip_count + max_depth + *min_dropped_frames.

== Return Value

The number of frames stored in `result` and `sizes`.

== Parameters

[cols="1,4"]
|===
| Name| Description
| *result*
| Buffer to receive the recorded program counter values.
| *sizes*
| Buffer to receive the corresponding stack frame sizes.
| *max_depth*
| Maximum number of frames to record.
| *skip_count*
| Number of most recent stack frames to skip.
| *uc*
| Pointer to the signal handler's `ucontext_t` value, or null.
| *min_dropped_frames*
| If non‐null, receives the number of stack frames dropped.
|===


[.small]#Created with https://www.mrdocs.com[MrDocs]#