Tornado Reference : Tornado Utilities
xsymc - extract the symbol table from a COFF object module
xsymc < objMod > symTbl
This tool reads an object module (UNIX SYSV COFF format) from standard input and writes an object module to standard output. The output module contains only the symbol table, with no code, but is otherwise a normal, executable object module.
This tool is used to generate the VxWorks symbol table, vxWorks.sym.
ecoff.h - UNIX SYSV COFF object module header file
xsymc, makeSymTbl, UNIX SYSV COFF documentation