1. A semantic checker for Fortran 77 programs. ftnchek (short for Fortran checker) is a tool designed to detect certain errors in a Fortran program that a compiler usually does not, thus assisting users in the debugging of their Fortran programs. Unlike syntax errors, semantic errors are legal in the Fortran language but are wasteful or may cause incorrect operation. For example, variables which are never used may indicate some omission in the program; uninitialized variables contain garbage which may cause incorrect results to be calculated; and variables which are not declared may not have the intended type. ftnchek can also be used to provide call-trees, cross-reference of subprogram calls and COMMON blocks usage, source listings, symbol tables and other things you might find useful when debugging a Fortran program. From Debian 3.0r0 APT