[Mapserver-users] ESRI .prj and PROJ epsg

[Kieran J. Ames]

Is anyone aware of a means to translate ESRI's .prj files and find the
equivalent PROJ epsg entry?

eg:
GEOGCS["GCS_North_American_1983",
DATUM["D_North_American_1983",
SPHEROID["GRS_1980",6378137,298.257222101]],
PRIMEM["Greenwich",0],
UNIT["Degree",0.0174532925199433]]

How do I know what to assign to variables like
+proj=
+lat_1=
+lat_2=
+lat_0=
+lon_0=
+x_0=
+y_0=
+lonc=
+alpha=
+k=
+ellps=
+datum=
+units=
+no_defs
no_defs

THANKS!
Kieran