book

Exploring Expect

by Don Libes

December 1994

Intermediate to advanced

606 pages

16h 7m

English

O'Reilly Media, Inc.

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Expect—Why another tool?
Notational Conventions
Ouch, Those Programs Are Painful!

Testing
Important Reading MaterialOther BooksOther Online DocumentationSupport
Everything Is A String
Return ValuesPuts
The while CommandThe incr CommandThe for CommandThe if CommandThe switch CommandContinuation LinesThe break And continue CommandsThe proc And return CommandsThe source Command
Selecting Elements Of ListsVarying Argument ListsLists Of ListsCreating ListsThe list And concat CommandsBuilding Up Lists With The lappend CommandThe linsert CommandThe lreplace CommandThe lsearch CommandThe lsort CommandThe split And join Commands
The scan And format CommandsThe string CommandThe append Command
Variable InformationArray InformationUnsetting VariablesTracing Variables
Causing Errors
Evaluating Commands In Other Scopes
File Name MatchingSetting And Getting The Current DirectoryFile Name ManipulationFile Information
The send Command
The * Wildcard* At The Beginning Of A Pattern Is Rarely Useful* At The End Of A Pattern Can Be Tricky
Regular Expressions—A Quick Start
Matching Anything But
Pattern Debugging
The send_user Command
Securing Scripts By File ProtectionSecuring Scripts By Host Protection
Expect—Just Another Program
The Terminal Mode During The interpreter CommandThe interpreter PromptChanging The Prompt—prompt1 And prompt2Causing The interpreter Command To Return^DUsing interpreter In Production Scripts
The spawn_id Variable
Implicit Versus Explicit Spawn Ids
How Long Are expect_before And expect_after In Effect?Using expect_before And expect_after With The Currently Spawned Process—DANGERUndoing The Effects Of expect_before And expect_afterInformation On The Current expect_before And expect_after Patternsexpect_before And expect_after Actions
Indirect Spawn Ids—Are They Really That Useful?
Implicit Versus Explicit Spawn Ids
The Search Path
Signals
SIGINT—Software Interrupt SignalSIGTERM—Software Termination SignalSIGQUIT—Quit SignalSIGKILL—Kill SignalSIGCHLD—Child Termination SignalSIGHUP—Hangup SignalSIGPIPE—Broken Pipe SignalSIGWINCH—Window Size Change SignalSIGTSTP—Terminal-Generated Stop SignalSIGSTOP—Kernel-Generated Stop SignalSIGCONT—Continue SignalSIGUSR1 And SIGUSR2—User-Defined SignalsOther Signals
Avoiding Problems Caused By Signal Handlers
The interact Command
Connecting To A Process Other Than The Currently Spawned Process
How kibitz Works
Putting Expect In The Background
Telling The System About Your Daemon
Tracing
Breakpoint By Line Number And FilenameBreakpoint By ExpressionBreakpoint By Pattern MatchBreakpoint ActionsLimitations Of Breakpoint Actions And Interactive CommandsGeneral Form Of BreakpointsListing BreakpointsDeleting Breakpoints
Tk—A Brief Technical OverviewWidgetsOther Widgets And Naming ConventionsDisplaying WidgetsBindings And EventsThe Event Loop
Expectk Scripts
The term_expect Procedure
Encrypting A Directory
The tknewsbiff Script
Overview
Caching Regular Expressions
Adding Expect To Another Tcl-based Program
Shared VariablesNon-Shared Variables and Functions
Random Numbers
Commands And Flags

Content preview from Exploring Expect

Changing Program Behavior

When the debugger is active, the variable dbg is defined in the global scope. When the debugger is not active, dbg is not defined nor are the debugger commands such as s and n. This allows scripts to behave differently when the debugger is running.

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Publisher Resources

ISBN: 9781565920903Supplemental Content Errata Page