Textual information

This set of routines provide access to any textual information associated with the catalogue¹⁴. They try to keep access to the textual information as simple as possible. The text is accessed one line at a time, with each line corresponding, for example, to a single FITS COMMENT or HISTORY keyword. No facilities are provided to interpret a line. It is assumed that each line will either be displayed to the user or copied to another catalogue.

CAT_GETXT returns a single line of text. Subsequent calls to CAT_GETXT work sequentially through the textual information, returning the lines in sequence. The application cannot specify that it wants a particular line. However CAT_RSTXT is provided to `reset' the sequence for a catalogue, so that the textual information can be read through an arbitrary number of times.

Each line has a class associated with it. When a line is read the class is returned; an application cannot prescribe that it wants a class of a particular value. The classes supported vary for the different catalogue formats, though on output the standard classes COMMENT and HISTORY are always available. Appendix  lists the classes supported by individual catalogue formats.

A call to CAT_PUTXT appends a line of textual information to the end of the existing textual information for a catalogue. The only way to add new textual information is by appending it to the end.

In all these routines CI must be a catalogue identifier.

CAT_GETXT (CI; FINISH, CLASS, TEXT; STATUS)

 
Get the next line of textual information from a catalogue.

CAT_PUTXT (CI, CLASS, TEXT; STATUS)

 
Put a line of textual information to a catalogue.

CAT_RSTXT (CI; STATUS)

 
Reset the access to the textual information in a given catalogue. A subsequent call to CAT_GETXT would return the first line of textual information.

CAT_SZTXT (CI, ACCESS; LINESZ; STATUS)

 
Return the maximum permitted size of a line of textual information in a catalogue. The maximum size is determined by the format of the catalogue and the access mode (READ or WRITE).