a — Maximum number of entries held in the command line/read line recall buffer, subject to the space limitation in the second parameter. The range is 0–256 entries. The default is 32 entries.

b — Total size (in bytes) of all input strings to be stored in the command line/read line buffer. The range is 0–8192 bytes. The default is 1024 bytes.

For a, in the LineRecallEntries row, select Edit. Enter a number of entries.

For b, in the LineRecallBuffer row, select Edit. Enter a number of bytes.