bt_set_flags()

Set or clear the flags for backtracing

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The backtrace library is an unsupported feature, due to its fragility. For more information, see Backtraces in the QNX Neutrino technotes.

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Synopsis:

#include <backtrace.h>

int bt_set_flags( bt_accessor_t *acc,
                  unsigned flags,
                  int onoff );

Arguments:

acc

A pointer to a bt_accessor_t structure. This is an opaque structure that holds the identity of the thread to backtrace.

flags

A bitwise ORing of the flags you want to set:

• BTF_LIVE_BACKTRACE — typically bt_get_backtrace() freezes a thread before gathering the backtrace. If you set this flag, bt_get_backtrace() doesn't freeze the thread. This can be useful if you want to freeze many threads at the same time, and then collect the backtrace for all threads, thus providing a coherent snapshot for all of the threads.

onoff

Zero to clear the specified flags, or a nonzero value to set the flags.

Library:

libbacktrace

Use the -l backtrace option to qcc to link against this library.

Description:

The bt_set_flags() function lets you turn the specified flags on or off.

Returns:

0

Success.

-1

An error occurred (errno is set).

Errors:

EINVAL

The flags argument specifies an invalid flag.

Classification:

QNX Neutrino

See also:

bt_get_backtrace(), bt_init_accessor(), bt_load_memmap(), bt_release_accessor(), bt_sprn_memmap(), bt_sprnf_addrs(), bt_translate_addrs(), bt_unload_memmap()

Backtraces in the QNX Neutrino technotes

pidin backtrace in the Utilities Reference