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Command Recalling

By default, the last 15 commands entered on the terminal are kept in an internal buffer (the no. of commands saved can be changed via SET/BUFFER). To recall (and execute) any of these commands, simply type the associated command number. This is the number ``xyz'' appearing in the prompt Midas xyz> when that command was entered. To display the command buffer, simply hit \fbox{\tt Return}.
If you want to recall more than one command at once, enter all the relevant command numbers (separated by a semicolon and space), e.g. enter 14; 17; 22 if you want to repeat the commands numbered 14, 17 and 22 . Also 14; read/keyw in_a; 17 is possible.
To recall commands not by number but by pattern, use :pattern to repeat the last command matching the specified pattern. For example, if the last two commands in your command buffer are:

22 READ/IMAGE supernova
23 show/commands
Then, typing 22 as well as :READ or :nova will execute the command READ/IMAGE supernova again. Note that for the pattern matching MIDAS does make a distinction between upper and lower case.
You can also use the vertical arrow keys to navigate up and down through the command buffer.   
Besides repeating complete input lines it is also possible to just use parts of the last command line. Each ``token''  of the last command line is saved internally until the next input. A ``token'' is the information separated by spaces in the command line. To repeat the tokens on a subsequent command line merely type a `.' For example, if you have in the command buffer:
LOAD/IMAGE myframe 0 2,2
Then typing ` . yourframe . . ' as the next command is equivalent to typing `LOAD/IMAGE yourframe 0 2,2'.
All features described so far apply to genuine MIDAS commands as well as to host system commands (where the first character of the command line is the $ sign).
Some words of caution: In VMS the version number of files may be specified using a semicolon, e.g.
$ RENAME file.typ;7 lola.bdf.
Typing such a command inside MIDAS will not work, since the monitor will interpret this input as two Midas commands. Instead, use a dot to separate the version number, e.g.
Midas 234> $ RENAME file.typ.7 lola.bdf. In Unix the repetition of tokens may cause trouble. Consider the following:
Midas 123> load/image vaca
Midas 124> $cp /elsewhere/toro.bdf .
The intention was to simply copy the file toro.bdf from somewhere else to the current directory. But instead of toro.bdf you will find a strange file named ? in your directory...
In the line `123' only two tokens are entered, so all other 8 tokens are set to the default value `?'. In line `124' the third token will be set to the third token in the line above, so it changes to:
Midas 124> $cp /elsewhere/toro.bdf ?
Instead, specify also the result frame completely, e.g.
$cp /elsewhere/toro.bdf toro.bdf. Preceding a host command by $$ disables the interpretation of specific symbols by MIDAS, thus
Midas 124> $$cp /elsewhere/toro.bdf .
will actually do the expected copy.

next up previous contents index
Next: Command Line Editing Up: Command Syntax Previous: Command Syntax
Petra Nass