Read:

These are only called through cdds_read.

Files:
    f_xxx.c      - Fortran API Routines
                      f_readm.c f_read.c
    c_xxx.c      - "C" API Routines
                      c_readm.c c_read.c
    readuspl.c   - Read usp line header binary data
    readuspt.c   - Read and edit usp trace binary data
    readsegyc.c  - Read segy card header binary data
    readsegyb.c  - Read segy binary header binary data
    readsegyt.c  - Read and edit segy trace binary data
    readgent.c   - Read and edit generic trace binary data
    readgen.c    - Read generic binary data on a byte-basis
    readslicet.c - Read and edit sliced trace binary data
    readslice.c  - Read sliced binary data on a byte-basis
    readcheck.c  - Check results of read binary data
                   (residual bytes, EOF, padding...)