scancontext ?option?
This command manages file scan contexts. A scan
context is a collection of regular expressions and
commands to execute when that regular expression
matches a line of the file. A context may also
have a single default match, to be applied against
lines that do not match any of the regular expres-
sions. Multiple scan contexts may be defined and
they may be reused on multiple files. A scan con-
text is identified by a context handle. The scan-
context command takes the following forms:
scancontext create
Create a new scan context. The scanmatch command
is used to define patterns in the context. A con-
texthandle is returned, which the Tcl programmer
uses to refer to the newly created scan context in
calls to the Tcl file scanning commands.
scancontext delete contexthandle
Delete the scan context identified by contex-
thandle, and free all of the match statements and
compiled regular expressions associated with the
specified context.
scancontext copyfile contexthandle ?filehandle?
Set or return the file handle that unmatched lines
are copied to. (See scanfile). If filehandle is
omitted, the copy file handle is returned. If no
copy file is associated with the context, {} is
returned. If a file handle is specified, it
becomes the copy file for this context. If file-
handle is {}, then it removes any copy file speci-
fication for the context.
This command is provided by Extended Tcl.