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UNW_REG_STATES_ITERATE(3) Programming Library UNW_REG_STATES_ITERATE(3)
NAME
unw_reg_states_iterate -- get register state info on current procedure
SYNOPSIS
#include <libunwind.h>
int unw_reg_states_iterate(unw_cursor_t *cp, unw_reg_states_callbackcb,
void *token);
DESCRIPTION
The unw_reg_states_iterate() routine provides information about the
procedure that created the stack frame identified by argument cp. The
cb argument is a pointer to a function of type unw_reg_states_callback
which is used to return the information. The function
unw_reg_states_callback has the following definition:
int ( *unw_reg_states_callback)(void *token, void *reg_states_data,
size_t reg_states_data_size, unw_word_t start_ip, unw_word_t end_ip);
The callback function may be invoked several times for each call of
unw_reg_states_iterate. Each call is associcated with a instruction
address range and a set of instructions on how to update register
values when returning from the procedure in that address range. For
each invocation, the arguments to the callback function are:
void * token
The token value passed to unw_reg_states_callback.
void * reg_states_data
A pointer to data about updating register values. This data, or
a copy of it, can be passed to unw_apply_reg_state.
int reg_states_data_size
The size of the register update data.
unw_word_t start_ip
The address of the first instruction of the address range.
unw_word_t end_ip
The address of the first instruction beyond the end of the
address range.
RETURN VALUE
On successful completion, unw_reg_states_iterate() returns 0. If the
callback function returns a nonzero value, that indicates failure and
the function returns immediately. Otherwise the negative value of one
of the error-codes below is returned.
THREAD AND SIGNAL SAFETY
unw_reg_states_iterate() is thread-safe. If cursor cp is in the local
address-space, this routine is also safe to use from a signal handler.
ERRORS
UNW_EUNSPEC
An unspecified error occurred.
UNW_ENOINFO
the access_mem() call-back (see unw_create_addr_space(3)).
SEE ALSO
libunwind(3), unw_apply_reg_state(3)
AUTHOR
David Mosberger-Tang
Email: dmosberger@gmail.com
WWW: http://www.nongnu.org/libunwind/.
Programming Library 16 August 2017 UNW_REG_STATES_ITERATE(3)