file_spec"n" does not recognize a non-numeric "n"

If, for example a file_spec_abcdef given, the sosftp-client takes this as a multipe file_spec.

the syntax for this is "file_spec2=" all non-numeric charcters for "n" must give an error.

All other tries to specify a multiple file_spec parameter will procuduce an error.

• In addition to what is stated for the parameter file_spec additional parameters
  can be specified for up to 9 file sets like this:

-file_spec=.*\.gif$ -local_dir=/tmp/1 -remote_dir=/tmp/1
-file_spec2=.*\.exe$::param_set_2 -param_set_2="transfer_mode=binary::remote_dir=/tmp/2::local_dir=/tmp/2"

Within the file_spec2 parameter value the regular expression is separated by ::
from the name of a file set. This name can freely be chosen, it consists of the
characters 0-9, a-z and _.

The name of the file set is used as a separate parameter in the command line.
This parameter is assigend the list of parameters that should be valid for the specific file set.
Therefore the names and values of individual parameters are specified in the form
name=value::name2=value2 .... Such parameters are exclusively valid for the specific file set.

The above sample causes all files with the extension .gif to be transferred from
the local directory /tmp/1 to a directory with the same name on the target host.
For files with the extension .exe a file set param_set_2 is specified
that contains parameters that are specific for this file set, as binary transfer and
different source and target directories.

Please, consider that parameter file sets cannot specify parameters that control the
connection to a target host, i.e. all files are transferred between the same local and remote hosts.
However, the transfer direction can be changed, e.g. by specifying a different operation
parameter for a file set.