z/OS has both MVS datasets, and Hierarchical File System (HFS) files. As both types must be accessed by the SFTP server, there must be a mechanism for distinguishing between them. Traditionally, MVS datasets in z/OS are accessed using the filename format
//'NAME.OF.MVS.DATASET', while HFS files are accessed using the filename format
In z/OS, if a dataset name is not enclosed in single quotes, the user prefix is added in front of the dataset name. For example, if user
USER1 has a dataset
DATASET.NAME1, the user can access it using the dataset name
//DATASET.NAME1. It is also possible to use an absolute prefixed name
z/OS has also library datasets, whose members are accessed using the dataset name
SSH Tectia Server for IBM z/OS will not mount volumes or consider off-line devices when accessing datasets, instead it will issue an error message if the dataset is in the catalog but the volume is not available.