Downloading Multiple Files Via Import and FTP

[Gregory Lypny]

Hello everyone,

Mathematica's Import function works well for downloading single files from a remote computer using ftp, but it gets stuck when downloading anything more than about a 20 files in succession, even when those files are just few bytes.

If I define the path to a folder on my remote mac as

ftpPath="ftp://user:password@domainName//filePath/=93

I can easily download a single file, myFile, using

Import[ftpPath<>myFile, "CSV=94]

But if I try to download, say, 60 small files whose names are contained in myFileNames by mapping across the names (or by using Table)

Import[ftpPath<> #, "CSV=94] &/@ myFileNames

I get two errors: (1) URLFetch::invhttp : Failure when receiving data from the peer; and (2) FetchURL::conopen.

I thought that maybe Mathematica was sending in the requests too quickly, so I tried slowing things down by inserting a one-second pause between each call to Import but that didn't help. Maybe I have to close a socket between each import but I don't know how to do that.

Anyone know of a fix?

Much obliged,

Gregory

[Roland Franzius]

Uploading and downloading many files or a very large file using a
ftp-browser like fileZilla, in the protocoll window you observe that the
server rather often breaks the connection.

Its the browsers duty to reconnect and and resume the broken transfer
session.

The rather short connection timeout seems to be a security feature of
ftp servers against automated data suction. The ftp password security is
an illusion, it applies to the naive users only.

--

Roland Franzius