libexc(3F)

NAME
     trace_back_stack, trace_back_stack_and_print - call stack trace library
     for Fortran applications

SYNOPSIS
     integer*4 trace_back_stack
     integer*4 i
     integer*8 addrs(100)
     character*100 names(100)
     i = trace_back_stack(0, addrs, names,
                                   100, 100)

     call trace_back_stack_and_print()

     integer*8 addr, entry
     character*100 name
     call exc_dladdr(addr, name, 100, entry)

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).

SEE ALSO
     speedshop(1), libexc(3)

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.