Command Structure

ictrans commands have a simple and regular structure. Commands which operate directly on the metafile being processed may be preceded by a frame_list which designate the frames to which the command applies. Some commands accept arguments. Anything following a command name is regarded as an argument:

A comma-separated pair of frames implies the inclusive list of frames. If a frame list is omitted and a command requires a frame then the current frame is used as the default. If no argument list is specified and one is required then a default argument is used whenever possible.

For example, the command 1,5 8 save /tmp/foo would write the first through fifth and the eighth frame of the metafile to the file /tmp/foo.

Commands will ignore any unexpected arguments. Command names may be abbreviated up to the point that they are unique.

Frame Lists

Frames can be addressed in several ways:

nnn

By frame number. Frames are assigned a relative number from first to last in the metafile. The first frame is numbered 1.

$

The last frame in the file.

.

The current frame. ictrans keeps track of the last frame upon which an operation was performed. This frame is called the "current frame".

frame+-n

A frame number followed by a plus sign (+) or a minus sign (-), followed by a decimal number, specifies the frame plus or minus the indicated number of frames. frame may be omitted in which case the current frame is assumed. For example, `10+2' addresses frame 12 in the metafile.

Commands

! command
Run command as a shell command on the local machine.

alias [ name [ def ] ]
Assign def to the alias name. If def is omitted, the alias name is displayed along with its current definition. If both name and def are omitted, all aliases are displayed. def is of the form:

: [ ctrans_args ] : [ filter_chain ]

where ctrans_args is list of command line arguments for the metafile translator ctrans and filter_chain is a set of simple commands separated by |. filter_chain may be terminated by > or >> filename. For example:

ictrans> alias name1 : -d xwd : | cat > outfile

or

ictrans> alias name2 : -d ps.mono : | filter1 | lpr

dup [number]
This command is used to set the number of times each frame is displayed during subsequent plotting. The default is one. If dup is invoked without any arguments the current value of dup is returned.

count
Reports number of frames contained in the file.

current
Reports the current frame.

file [ metafile ]
The file metafile will be used for subsequent translation. ictrans uses the shell defined by the environment variable SHELL (/bin/sh by default) to perform filename substitution on metafile. The rules governing filename substitution are as defined by the working shell. If no argument is given the current metafile name is reported.

font [ font ]
Set the fontcap to font for future translation. This function is identical to that of the -font option. If font is omitted the current fontcap name is reported.

help [ command ]
Print a usage statement for command. If command is omitted a brief description of all commands is given.

[ frames ] list
Provide brief information about each metafile frame in frames. If frames is omitted then the current frame is used. If frames is omitted and the current frame is not the last frame then the current frame is incremented to the next frame in the metafile.

< frame1 > < frame2 > merge
Plot frame number frame1 and then plot frame number frame2 over the first frame without clearing the device. The result is a "merge" of the two plots. The current frame is not changed. There are no defaults for frame1 or frame2. The resulting plot might not be what was expected. Attributes from the first frame, such as color, may override attributes in the second frame.

loop
Toggle loop mode on or off. When loop mode is on subsequent plot commands will cause the requested frames to be plotted and then ictrans will proceed to either the first frame in the defined segment or the last and repeatedly display the first through last (last through first) frames. Looping continues until an interrupt signal is received. The determination of which order to loop, forwards or backwards, is made as follows: If the last group of frames plotted was in ascending order loop forward. If the last group of frames plotted was in descending order loop backwards. If the order cannot be determined don't loop. For example; if loop mode is set "1 3,4 plot" will result in forward looping, "1 4,3 plot" will result in backward looping, and "3,4 1 plot" will result in no looping because the last group of frames plotted, "1", is a single frame.

movie [ time ]
Display each frame for time seconds before proceding to the next frame during subsequent plots. If time is omitted then movie mode is toggled off or on. In the case the movie mode is toggled on the default time is zero seconds. If movie mode is toggled to off a newline must be received before advancing to the next frame during plotting.

next
Multiple files may be specified on the ictrans command line. To edit the next file in the argument list use the next command.

[ frames ] plot
Plot the addressed frames. If frames is omitted then the current frame is plotted and if possible, the current frame number is incremented. If "movie" mode is set ictrans will wait time seconds after displaying each plot before continuing. time is set with the movie command. If "movie" mode is not set ictrans will wait for a newline character before advancing to the next frame. plot will report the number of frames and the last frame in frames. Plotting will be terminated and ictrans will reenter command mode after the last frame is plotted or upon receiving a interrupt signal, SIGINT.

[ frames ] Print
The addressed frames are translated and sent to the current spooling device. Translation is performed by a spawned translator. The spooler command may be used to select a spooling device. See ncarv_spool(5NCARG).

quit
Terminate the session.

[ frames ] save [ metafile ]
Save the addressed frames to metafile. If metafile does not exist then it is created. Filename substitution is performed on metafile. If metafile is omitted than the last file saved to is used. If frames is omitted than the current frame is used.

[ frames ] Save [ metafile ]
Same as the save command except Save does not confirm its actions with the user in the case that the file exists. If the file exists but is not a valid NCGM it is overwritten. If the file exists and is a valid NCGM it is appended to.

skip [ number ]
Set number of frames to skip over during subsequent plotting. For example, if "skip" is set to 1 and a request is made to plot frames 1 through 10 frames 1, 3, 5, 7, and 9 will be displayed. With no arguments skip reports its current value. The default is zero.

spooler [ spooler_alias ]
With no arguments the current spooler alias name is reported. If spooler_alias is a valid alias either defined by the alias command, or in a ncarv_spool configuration file, or by the NCARV_SPOOL environment variable, then spooler alias becomes the current spooler. Subsequent Print commands will use the spooler definition defined by the current spooler. See ncarv_spool(5NCARG).

[ start frame ] start
This command defines the first frame in a segment of frames. start, together with the stop command, define the boundaries of a segment of metafile frames. When ictrans is in loop mode the contents of this segment are repeatedly displayed. The default start frame is the first frame in the metafile, 1. If no arguments are given start reports the first frame in the current segment.

[ stop frame ] stop
This command defines the last frame in a segment of frames. The default stop frame is the last frame in the metafile, $. If no arguments are given stop reports the last frame in the current segment.

zoom [ llx [ lly [ urx [ ury ]]]]
The zoom command allows for specification of a workstation window (in the GKS sense). Four coordinates are specified which define a rectangular window which is a subset of the normalized VDC rectangle with corner points (0.0, 0.0) and (1.0, 1,0). The specified window is then mapped onto the entire viewport. For example

ictrans> zoom 0.0 0.0 0.5 0.5

would result in the lower left quarter of subsequent plots being blown up to fill the entire display. Specification of such a window may be used for zooming and panning.

The range with which one may zoom in on a plot may be limited by the integer addressing precision of the device.