The UEDTB1 module is a table of two-character library codes and information about the associated libraries. At invocation time, the utility programs UED, UEDIT, USERV, and UPDS load module UEDTB1. Each of these utility programs passes to its respective user-written exit routine a pointer to an entry in this module, if a two-character library code was used when accessing a library.
The following DSECT summarizes the format of each entry.
| Location | Length | Format | Contents | |
|---|---|---|---|---|
| Dec | Hex | |||
| 0 | 0 | 2 | Binary | Length of this entry (includes user data field) |
| 2 | 2 | 2 | Character | Library code |
| 4 | 4 | 6 | Character | Volume serial number, unless cataloged |
| 10 | A | 2 | Binary | Sequence number columns: First byte - Start column Second byte - End column |
| 12 | C | 2 | Binary | Tag number columns: First byte - Start column Second byte - End column |
| 14 | E | 10 | Binary | Paired bytes indicating start and end columns for the UED list function |
| 24 | 18 | 10 | Binary | UED tab stop columns |
| 34 | 22 | 1 | Binary | Access method: x'8x' - no user data display x'4x' - no user data stow x'2x' - input only x'x0' - LIBRARIAN x'x1' - Sequential x'x2' - PANVALET x'x3' - LIBRARIAN |
| 35 | 23 | 1 | Binary | DSN length, minus one |
| 36 | 24 | xx | Binary | User data field xx = maximum of 176 |
| aa | bb | 44 | Character | File name aa = 36 + xx bb = aa in hexadecimal |