motif

NAME
        motif

SYNOPSIS
        motif PATTERN

DESCRIPTION
        search for PATTERN in all files in the current directory whose suffix ends by .f, .F, .c, or .h
        Because Fortran files are case independent, the motif program search for patterns that are
        either lower case or upper case

Use case:

 $ motif implicit
amber2car.f:      implicit none 
checkinterdist.f:      implicit none
find_closest2.f:      implicit none
find_closest2.f:      implicit none
find_closest2.f:      implicit none
find_closest2.f:      implicit none
getmoving.f:      IMPLICIT NONE
mdcrdcenter-2.f:      implicit none
mdcrdcenter-2.f:      implicit none
mdcrdcenter-2.f:      implicit none
mdcrdcenter.f:      implicit none
mdcrdcenter.f:      implicit none
mdcrdcenter.f:      implicit none

Commands to include in your script: grep