file.control.block Definition/General

file.control.block

Command file.control.block Definition/General
Applicable release versions: AP
Category General (155)
Description defines a file control block.

Every file on the system has a special frame (or frames) attached to it called a "file control block" or "fcb". These frames contain information about the file, including index pointers and their compiled a (algebraic) processing codes, the file "d-pointer" information for editing, pointers and workspace used by the system when calling Pick/BASIC subroutines from file dictionaries.

Also contained in this "file control block" are important flags and fields indicating that the file is open, closed, in the process of being deleted, etc. This provides the ability to protect the system from potenitally disastrous situations, such as the case of one process deleting a file while another process is using the same file.
Syntax
Options
Example
Purpose
Related tcl.move-file
tcl.clear-file
basic.open
fcb
filename.file-of-files
tcl.steal-file
basic.common
tcl.list-file-stats
tcl.file-save
basic.close
tcl.account-save
tcl.delete-file
tcl.save
file.defining.items