Magic VLSI Layout Tool Version 8.2 *


Handle periodic backups during a layout editing session.


crashbackups [start|stop|resume|disable]


The crashbackups procedure enables or disables the periodic saving of crash recovery backup files. crashbackups or crashbackups start sets the timer for the first periodic save. After the timer times out, backup file is generated and written in the system temporary directory, and the timer is reset. By default, the backup interval is 10 minutes (600000 msec). The interval can be changed by setting the value of Tcl variable $Opts(backupinterval) to the interval value in msec.

crashbackups stop removes the timer callback and thus prevents further writing of backup files. Note that if crash recovery is stopped or started multiple times during a session, the same filename is used to save the data.

crashbackups resume resumes running interval backups if stopped using crashbackups stop. If the interval backups have never been started, or have been disabled, this command does nothing.

crashbackups disable stops running interval backups and resets to the state of never having started interval backups. resume will have no effect in this state, and start must be issued to start the interval backups again.

Implementation Notes:

crashbackups is implemented as a Tcl procedure in the "tools.tcl" script file. It calls the magic command "crash save".

The crash backup interval is handled by the itimer system subroutine. There is only one timer per process. A timer is also used by some long-running commands such as extract to track progress, so the crash backups must necessarily be suspended when those commands are using the process timer.

See Also:


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Last updated: March 17, 2021 at 10:53am