Sonim AT Commands

Filesystem access:

at*list=<path> - list directory content
                                     (0=file, 1=subdirectory)
at*mkdir=<path> - make directory
at*rmdir=<path> - remove directory
at*remove=<path> - remove file
at*move=<srcpath>,<dstpath> - ? copy (move?) files
at*startul=<srcpath> - prepare file to upload (from phone)
                                     returned data:
                                     *STARTUL: <filesize_in_bytes>
at*startdl=<dstpath>,<filesize> - prepare file to download (to phone)
at*get - get base64 coded data chunk
                                     returned data:
                                     *GET: <chunklen>,<data>
at*get - get base64 coded data chunk
                                     returned data:
                                     *GET: <chunklen>,<data>
at*put=<no>,<len>,<data>,<chck> - put base64 coded data chunk
                                     (no is chunk number, starting from 0)
                                     (len is chunk length)
                                     (last 4 characters is checksum ?)
at*end - end/finish file transfer operation
at*syph=?,?.?,<path> - ? (add downloaded record to phonebook?)
at*sysm=0,1,%d - ? SMS handling

Phone has at least two directories from root, /app and /app3 .
at*list=/ gives error.