<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<!--Converted with LaTeX2HTML 98.1p1 release (March 2nd, 1998)
originally by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds
* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan
* with significant contributions from:
Jens Lippmann, Marek Rouchal, Martin Wilck and others -->
<HTML>
<HEAD>
<TITLE>Command Syntax</TITLE>
<META NAME="description" CONTENT="Command Syntax">
<META NAME="keywords" CONTENT="vol1">
<META NAME="resource-type" CONTENT="document">
<META NAME="distribution" CONTENT="global">
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<LINK REL="STYLESHEET" HREF="vol1.css">
<LINK REL="next" HREF="node37.html">
<LINK REL="previous" HREF="node25.html">
<LINK REL="up" HREF="node22.html">
<LINK REL="next" HREF="node32.html">
</HEAD>
<BODY >
<!--Navigation Panel-->
<A NAME="tex2html870"
HREF="node32.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next"
SRC="icons.gif/next_motif.gif"></A>
<A NAME="tex2html866"
HREF="node22.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up"
SRC="icons.gif/up_motif.gif"></A>
<A NAME="tex2html860"
HREF="node30.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous"
SRC="icons.gif/previous_motif.gif"></A>
<A NAME="tex2html868"
HREF="node1.html">
<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents"
SRC="icons.gif/contents_motif.gif"></A>
<A NAME="tex2html869"
HREF="node216.html">
<IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index"
SRC="icons.gif/index_motif.gif"></A>
<BR>
<B> Next:</B> <A NAME="tex2html871"
HREF="node32.html">Command Recalling</A>
<B> Up:</B> <A NAME="tex2html867"
HREF="node22.html">Monitor and Command Language</A>
<B> Previous:</B> <A NAME="tex2html861"
HREF="node30.html">Specifying Sub-Image</A>
<BR>
<BR>
<!--End of Navigation Panel-->
<H1><A NAME="SECTION00640000000000000000"> </A><A NAME="1578"> </A>
<A NAME="command-syntax"> </A>
<BR>
Command Syntax
</H1>
<P>
After start-up, the MIDAS monitor prompts you to interact with MIDAS
by entering commands on the terminal which are terminated by
<!-- MATH: $\fbox{\tt Return}$ -->
<IMG
WIDTH="83" HEIGHT="27" ALIGN="BOTTOM" BORDER="0"
SRC="img17.gif"
ALT="\fbox{\tt Return}">(Enter key).
<BR>
To enter a command-line on more than one terminal/window line, use
the continuation character, a minus sign (<TT>-</TT>), as the last character of a
line. The command line is limited to 400 characters.
If you want to enter more than one command on a single line, separate the
commands with a semicolon and space (<TT>;</TT> ).
<BR>
A MIDAS command line is structured as <BLOCKQUOTE>
<TT>command/qualifier par1 par2 ... par8 !comments</TT></BLOCKQUOTE>The command<A NAME="1584"> </A> describes the general action you want to perform (a verb) and
the qualifier<A NAME="1585"> </A> usually specifies the object of that action, e.g.
<TT>WRITE/DESCRIPTOR</TT>.
The (at most) 8 command parameters have a max. length of 100 chars. and
hold all other information needed to perform the
required action. All parameters are separated by spaces.
<BR>
<BR>
Currently the following ``objects'' exist in MIDAS:
<UL>
<LI>keywords<A NAME="1588"> </A>
<LI>descriptors<A NAME="1589"> </A>
<LI>bulk data frames
<UL>
<LI>images<A NAME="1591"> </A>
<LI>tables<A NAME="1592"> </A>
<LI>fit files<A NAME="1593"> </A>
<LI>ASCII files
</UL>
<LI>catalogs<A NAME="1595"> </A>
<UL>
<LI>for images
<LI>for tables
<LI>for fit files
</UL>
<LI>auxiliary image-display data structures (where applicable)
<UL>
<LI>LUTs (Colour Look-Up Tables)
<LI>ITTs (Intensity Transfer Tables)
<BR>
(internally these structures are stored in MIDAS table files)
</UL></UL>
<P>
<BR>
All user input and output from MIDAS commands is recorded in an ASCII
file, named FORGRxy.LOG (with <TT>xy</TT> the MIDAS unit) and stored in the
<TT>MID_WORK</TT> directory. This MIDAS logfile<A NAME="1603"> </A>
serves as a hardcopy of a full MIDAS session. Terminating MIDAS with <TT>BYE</TT>
and continuing later on via <TT>gomidas</TT> will not restart a new logfile
but append to the existing one.
The logging in MIDAS
can be
controlled via commands like <TT>LOG/OFF, LOG/ON, LOG/TOF, DELETE/LOG</TT>.
<BR>
Comments<A NAME="1607"> </A> may be appended to the command string and are separated by at
least one white space and <TT>`!'</TT> (exclamation mark) from it.
To give a complete line of comments, enter <TT>`!'</TT> as the first character
of the input line (useful for structuring the contents of
the MIDAS logfile).
Commands<A NAME="1610"> </A> and qualifiers<A NAME="1611"> </A> may be abbreviated to the number of significant
characters needed to distinguish them from the rest. At most 6 characters
are necessary for the command and 4 characters for the qualifier.
Command and qualifier are separated by a <TT>`/'</TT> (slash).
Nearly all
commands need a qualifier, but there is only one qualifier per command
(e.g. <TT>comm/qual1/qual2</TT> is unsupported in MIDAS).
In case you omit the qualifier, the default qualifier of that command is used
by MIDAS.
The default qualifier of a MIDAS command <I>mycomnd</I> may be displayed via
<TT>SHOW/COMMAND mycomnd</TT>. For example, the default qualifier for the
<TT>LOAD</TT> command is <TT>IMAGE</TT>, so typing <TT>LOAD/IMAGE</TT> or
<TT>LOAD</TT> will have the same effect.
The parameters<A NAME="1620"> </A> depend on the actual command.
A space (blank) is the delimiter<A NAME="1621"> </A> for parameters in the command-line.
Commas are used to subdivide parameters. If you need a space inside a parameter,
this parameter has to be enclosed in double quotes (").
<BR>
Normally, parameters are position dependent, i.e. <TT>par1</TT> is the first,
<TT>par2</TT> the second, and so on. This may be overridden by using the following
syntax:<BLOCKQUOTE>
<TT>command/qualifier P4=par4 P1=par1 P7=par7 ... !comments</TT></BLOCKQUOTE> <BR>
If the command procedure which is activated by a MIDAS command uses the
<TT>CROSSREF</TT> command, it is also possible to execute that command via:<BLOCKQUOTE>
<TT>command/qualifier label4=par4 label1=par1 label7=par7 ... !comments</TT></BLOCKQUOTE>The help text of each command specifies whether such a cross referencing
of parameters is possible and if so, which labels to use.
For details about the command <TT>CROSSREF</TT> see the description of it in
the section below on MIDAS procedures.
<BR>
<BR>
Whenever possible parameters have defaults. If you do not want to override them
use the symbol `?' (question mark) for a parameter if you use the position
dependent format. Therefore,
<BR>
<TT>command/qualifier P4=22.345</TT> is equivalent to <BR>
<TT>command/qualifier ? ? ? 22.345</TT> <BR>
The preset default values of MIDAS commands can be overridden with
<TT>CREATE/DEFAULTS</TT>. For example, the default for the descriptor name(s)
in the <TT>READ/DESCR</TT> command is
<TT>NAXIS,NPIX,START,STEP,IDENT,CUNIT,LHCUTS</TT> for an image frame. Thus,
typing
<BR>
<TT>Midas 234> READ/DESCR myimage</TT>
<BR>
will display the contents of the descriptors NAXIS, NPIX, START, STEP, IDENT,
CUNIT and LHCUTS of image <TT>myimage.bdf</TT>. After changing this default via
<BR>
<TT>Midas 235> CREATE/DEFAULTS READ/DESCR ? HISTORY</TT>
<BR>
the same command <BR>
<TT>Midas 236> READ/DESCR myimage</TT>
<BR>
will display the contents of the descriptor HISTORY of <TT>myimage.bdf</TT>.
<BR>
<P>
To abort<A NAME="1640"> </A> a MIDAS command, use
<!-- MATH: $\fbox{\tt Ctrl/C}$ -->
<IMG
WIDTH="83" HEIGHT="31" ALIGN="BOTTOM" BORDER="0"
SRC="img22.gif"
ALT="\fbox{\tt Ctrl/C}">(sometimes you also have to hit
<!-- MATH: $\fbox{\tt Return}$ -->
<IMG
WIDTH="83" HEIGHT="27" ALIGN="BOTTOM" BORDER="0"
SRC="img23.gif"
ALT="\fbox{\tt Return}">),
which will return control to you. <BLOCKQUOTE>
<DIV ALIGN="CENTER">
<B>Note</DIV>
<I>Be careful when aborting commands which interact with a display/graphics
window in the X11-Environment. For, you run the risk of losing the
synchronisation with the MIDAS
display server, which must then be re-initialized via
<TT>RESET/DISPLAY</TT> (see chapter 6 for details).</I></B></BLOCKQUOTE>
<BR><HR>
<!--Table of Child-Links-->
<A NAME="CHILD_LINKS"> </A>
<UL>
<LI><A NAME="tex2html872"
HREF="node32.html">Command Recalling</A>
<LI><A NAME="tex2html873"
HREF="node33.html">Command Line Editing</A>
<LI><A NAME="tex2html874"
HREF="node34.html">Command Line Suspension</A>
<LI><A NAME="tex2html875"
HREF="node35.html">On-Line Help</A>
<LI><A NAME="tex2html876"
HREF="node36.html">Input/Output Redirection in Midas</A>
</UL>
<!--End of Table of Child-Links-->
<HR>
<!--Navigation Panel-->
<A NAME="tex2html870"
HREF="node32.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next"
SRC="icons.gif/next_motif.gif"></A>
<A NAME="tex2html866"
HREF="node22.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up"
SRC="icons.gif/up_motif.gif"></A>
<A NAME="tex2html860"
HREF="node30.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous"
SRC="icons.gif/previous_motif.gif"></A>
<A NAME="tex2html868"
HREF="node1.html">
<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents"
SRC="icons.gif/contents_motif.gif"></A>
<A NAME="tex2html869"
HREF="node216.html">
<IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index"
SRC="icons.gif/index_motif.gif"></A>
<BR>
<B> Next:</B> <A NAME="tex2html871"
HREF="node32.html">Command Recalling</A>
<B> Up:</B> <A NAME="tex2html867"
HREF="node22.html">Monitor and Command Language</A>
<B> Previous:</B> <A NAME="tex2html861"
HREF="node30.html">Specifying Sub-Image</A>
<!--End of Navigation Panel-->
<ADDRESS>
<I>Petra Nass</I>
<BR><I>1999-06-09</I>
</ADDRESS>
</BODY>
</HTML>
