gdb.info: Prompt

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Prompt

GDB indicates its readiness to read a command by printing a string
called the "prompt".  This string is normally `(gdb)'.  You can change
the prompt string with the `set prompt' command.  For instance, when
debugging GDB with GDB, it is useful to change the prompt in one of the
GDB sessions so that you can always tell which one you are talking to.
   _Note:_  `set prompt' does not add a space for you after the prompt
you set.  This allows you to set a prompt which ends in a space or a
prompt that does not.
`set prompt NEWPROMPT'
     Directs GDB to use NEWPROMPT as its prompt string henceforth.
`show prompt'
     Prints a line of the form: `Gdb's prompt is: YOUR-PROMPT'