Wanted: Stand-alone FFT filter for UNIX

[Sascha du Lac]

Wanted: stand-alone FFT filter for unix

Could someone direct me to a stand-alone fft filter for the unix
environment?
I would like to be able to pipe it data and have it return the real and
complex
values of the input signal at each frequency (up to some reasonable range
of
frequencies).

Thank you,

Sascha du Lac
sascha at phy.ucsf.edu