#### 27.2.1 gdb/mi Input Syntax

command`==>`
  cli-command`|` mi-command
cli-command`==>`
  `[` token`]` cli-command nl, where cli-command is any existing gdb CLI command.
mi-command`==>`
  `[` token`] "-"` operation`( " "` option`)* [ " --" ] ( " "` parameter`)*` nl
token`==>`
  "any sequence of digits"
option`==>`
  `"-"` parameter`[ " "` parameter`]`
parameter`==>`
  non-blank-sequence`|` c-string
operation`==>`
  any of the operations described in this chapter
non-blank-sequence`==>`
  anything, provided it doesn't contain special characters such as "-", nl, """ and of course " "
c-string`==>`
  `"""` seven-bit-iso-c-string-content`"""`
nl`==>`
  `CR | CR-LF`

Notes:

- The CLI commands are still handled by the mi interpreter; their output is described below.
- The token, when present, is passed back when the command finishes.
- Some mi commands accept optional arguments as part of the parameter list. Each option is identified by a leading ``-`' (dash) and may be followed by an optional argument parameter. Options occur first in the parameter list and can be delimited from normal parameters using ``--`' (this is useful when some parameters begin with a dash).

Pragmatics:

- We want easy access to the existing CLI syntax (for debugging).
- We want it to be easy to spot a mi operation.