LIBEXC(3)LIBEXC(3)NAME
trace_back_stack, trace_back_stack_and_print - call stack trace library
SYNOPSIS
#include <libexc.h>
int trace_back_stack(int, __uint64_t *, char **,
int, int);
int trace_back_stack_and_print();
void exc_dladdr(__uint64_t, char *, int,
__uint64_t *);
DESCRIPTION
The libexc library provides the functionality for user-level call stack
unwind.
trace_back_stack is used to unwind the call stack at the time it's
called. The first argument sets the number of stack frames to be
unwound. If it's set to zero the unwind continues up to main or up to
_nsproc/_fork for child processes. The second argument is the array that
contains the addresses of the callers in the stack after the unwind is
completed. The third argument contains the names of the functions in the
stack after the unwind is completed. If this argument is set to NULL, it
disables procedure name extraction. The fourth argument is the size of
the array of callers and the fifth argument is the size of the procedure
name strings.
trace_back_stack_and_print unwinds the call stack (up to main or up to
_nsproc/_fork for child processes) and prints it to the standard output.
First, the pid of the process and the number of frames in the stack are
printed and then, for each frame, the program counter and the function
name.
exc_dladdr maps a text address to the procedure that includes it. The
first argument is the address to be mapped. The second argument will
contain the procedure name upon return and the third argument is the size
of the procedure name string. The fourth argument will contain the
procedure entry address upon return.
ENVIRONMENT VARIABLES
_LIBEXC_CACHE when set enables dwarf information caching (N32/N64 ABI's
only).
_LIBEXC_NO_PROC_NAME when set disables procedure name extraction (N32/N64
ABI's only).
_LIBEXC_INIT when set forces some dwarf information loading at the time
of the first call to the libexc functions (N32/N64 ABI's only).
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LIBEXC(3)LIBEXC(3)SEE ALSOspeedshop(1), libexc(3F)DIAGNOSTICS
Upon successful completion, both functions return the number of call
stack frames that were unwound. In the event of failure, a zero value is
returned.
NOTES
Executables complying to the o32 ABI have to be explicitly linked with
libexc.
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