links to this page:    Squeak Threading Model OSProcess Squeak Tutorials IOHandle TimeZone Dave Lewis All Projects Squeak, Cuis, Pharo compatibility issues - how to handle them CommandShell UnixDirectoryPlugin Hello World programs About the MagmaTester Squeak VM developers OSProcessPlugin AioPlugin Swiki Page List Project Ideas for Google Summer of Code 2007 Sake - A Squeak based make-like tool RemoteTask

2018 OSProcess 4.6.6

• OSProcess (this page, http://wiki.squeak.org/squeak/708)
• RemoteTask (http://wiki.squeak.org/squeak/6176)
• Overview of CommandShell (http://wiki.squeak.org/squeak/2153)
• CommandShell (http://wiki.squeak.org/squeak/1914)
• ExternalCommandShell (http://wiki.squeak.org/squeak/6023)
• ExternalPipe atEnd test

OSProcess Version 4.3.7 (November 24, 2008)

• At system shutdown, break dependency between ThisOSProcess and the OSProcessAccessor. This is done explicitly at shutdown in order to prevent possible problems when an image is restarted on another platform type, in which case a new ThisOSProcess instance is created and the old instance could still have an unwanted dependency on an OSProcessAccessor (bug found by Andreas Raab).
• Add WindowsProcess>>waitForCommand: implementation by Keith Hodges.

• On OS X, display management methods (e.g. #recapitate) and methods that require them (e.g. #forkSqueak) will not work. This is because an equivalent to XDisplayControlPlugin is not yet available for OS X.
• Stability and functionality of OSProcess on OS X is uncertain, as I do not have a Mac system available for testing (thanks to all who have helped testing via email).
• On Windows, OSPipe is implemented, but an OSPipe cannot yet be set for nonBlocking reads or writes. Reading from an OSPipe with no data available will block the Squeak VM.
• On Windows, command pipelines for external commands are not yet implemented. CommandShell does work, and may be used for launching individual Windows programs as well as for the usual CommandShell internal commands and internal command pipelines. However, it is not yet possible to construct a pipeline of Windows programs.
• Forking a child Squeak, as in UnixProcess>>forkSqueak, results in two instances of Squeak which share a single changes file. This has no practical impact if one or the other of the Squeak processes exits without doing very much, but it would could result in a corrupted changes file if both Squeak instances do a lot of changes. Any problems can be avoided by having one of the Squeak instances save itself as a new version, so that each instance uses its own image and changes files.
• The connectToXDisplay method is probably dangerous from a security perspective.

• Add patch from Jon Hylands to avoid problem moving images between Unix and Windows.

• Fix a concurrency problem in BufferedAsyncFileReadStream>>upToEndOfFile. This corrects intermittent failures detected in CommandShell test suite.

• Update reference to #listLoadedModules to work in newer Squeak versions.
• Update some default path strings for use in CommandShell.
• Removed separate version string for AioEventHandler.

• Provide backward compatibility with older versions of OSProcessPlugin.
• Fix bug in end of file test with older OSPP.

• Remove unnecessary synchronization semaphore from BufferedAsyncFileReadStream.
• Implement BufferedAsyncFileReadStream>>upTo:
• Fix underscores.
• Changed startup processing to reinitialize current OS process when image moves from one platform to another (e.g. image from Windows moved to Unix).
• Check installed OSPP version before calling pthread primitive to avoid error message when using older plugin.
• Add AttachableFileStream>>setBlocking and AttacheableFileStream>>setNonBlocking convenience methods.
• Better synchronization of buffer in BufferedAsyncFileReadStream.
• Add #killCurrentChildrenAtExit and #killOnVmExit:withSignal to arrange for child processes to be terminated on VM exit even if normal shutdown processing does not occur.
• Add accessor methods for Unix setsid(), getpgid(), setpgid(), getpgrp(), setpgrp() session management functions.
• Add modifications to StandardFileStream to package.
• Lower the priority of event handler process for AioEventHander to prevent input buffer being overloaded whens service process cannot keep up with input stream.

• Changes to support a fully event-driven CommandShell.
• Add StandardFileStream modifications to package.
• Change from underscores to ':=' for assignments.
• Win32OSProcessPlugin.dll is no longer distributed in this package.
• Fix #isAtEndOfFile: and add AttachableFileStream>>atEnd to make use of the fixed method. OSPP 4.2 has a fixed primitive that will be used if available, otherwise OSP works around the old bug.
• Add a nil check to AttachableFileStream>>atEnd.
• Reinstate methods required for backward compabibility with older CommandShell. Add new methods to implement improved #atEnd behavior, and #upToEndOfFile for pipes.
• Add buffered async behavior to file streams.
• Update OSPipe for event driven input.
• Update file locking to fix a bug and provide better error handling.
• Add fail blocks to file lock methods (versus e.g. test for nil).
• Add pthread instance variable to UnixProcess to display the identity of the pthread in which the interpreter is executing.
• File unlocking could fail if Win32 file locking emulation is disabled. This release fixes the problem. The problem can be demonstrated by evaluating 'OSProcessAccessor emulateWin32FileLocking: false' then running the UnixProcessFileLockingTestCase tests (or the UnixProcessWin32FileLockingTestCase and UnixProcessUnixFileLockingTestCase tests that replace them).
• Changed #saveImageInBackground to use a better time stamped image name.
• Added #saveImageInBackgroundNicely to do a background image save at lower priority.
• Fixed #uniqueNameForSavedImage to use leading zeros in date fields.
• Turn off Win32 file locking by default.
• Add a UnixProcess example for background processing.
• Clean up logic on OSFileLock>>test.
• Add pthread accessor for UnixOSProcessAccessor (requires OSPP 4.0.2).

• Add #nice: to set scheduling priority of the Squeak VM process.
• Add #forwardSigUsr1 and #forwardSigUsr2.
• Add methods for restoring original signal handlers, e.g. #restoreSigUsr1.

• Added 64-bit support. With OSPP 4.0 or greater, runs on a 64 bit VM, image, and/or 64 bit hardware. Backward compatibility is maintained for 32 bit platforms and earler VMMaker distributions.
• Added AIO classes previously distributed as part of the AIO package.
• Updated #allTestResults to tolerate missing plugins, update test for session ID, and provide better console output and results file.
• Fixed bit rot in Win32 classes.
• Added support for OS threads in Win32.
• Added Windows process access methods for primitives in OSPP 4.0.

• Refactored file lock management to provide clearer distinction between locks on file regions versus locks on entire files. Includes updates contributed by Julian Fitzell, who provided unit tests and various improvements to the file lock code.
• Made various changes and additions to OSProcessAccessor and UnixOSProcessAccessor to harvest additional improvements by Julian, and bring released version of OSP into sync with what Avi is using for Seaside applications.
• Added OSProcess class>>allTestResults
• Added UnixProcess class>>saveImageInBackground

• Refactored file lock management to provide clearer distinction between locks on file regions versus locks on entire files.
• Included updates contributed by Julian Fitzell, who provided unit tests and various improvements to the file lock code.

• Added support for KCP refactorings, in which a number methods were moved from SystemDictionary to SmalltalkImage. Backward compatibility is maintained for Squeak 3.6 and earlier.
• Changed class categories to work better with Monticello.
• Various minor cleanups and refactorings for file locking support.
• Added OSPipeprintOn: to avoid a problem that occurs when using the default Stream implementation.
• Updated #removeAllOSProcessAndCommandShellClassesFromSystem to handle new class categories.

• Update for Squeak 3.7. In particular, recent improvements to TestRunner flushed out some timing problems in OSProcess (especially in sUnit tests for CommandShell) which are now corrected in the child process reaper UnixOSProcessAccessorgrimReaperProcess.
• Rewrote primFork methods in both OSProcess and OSPP. This version of OSProcess uses the new primitives in OSPP 3.3 but maintains backward compatibility with earlier OSPP versions (at least back to OSPP 3.1.1). The child process creation methods for Unix now make use of the generic UnixProcessAccessorforwardSignal: signal forwarding mechanism rather than having the signal handlers coded in the individual process creation and pipe creation primitives in OSPP.
• If OSPP is compiled with -D_REENTRANT, OSProcess will probably now work on OS X, except for display management which is required for forkSqueak and friends.
• Better platform awareness for OS X.
• Rewrote file lock Win32 compatibility.
• Add class FileRegion to support Win32 file lock compatibility.

• Added support for Unix file locking (see the UnixOSProcessAccessor "file locking" method category).
• Generalized the logic for platform selection and added MacOS Unix/non-Unix conditions.
• Changed forkSqueak methods to fail gracefully if display management is not available.
• Removed obsolete method #primForkHeadlessSqueak.
• Fixed return value of #flushXDisplay.
• Some things are rumored to work on Mac OS X using the Unix VM.

• Download version 3.0 fromhttp://swiki.gsug.org:8080/sqfixes/2265.html.
• Apply this version 3.0.1 patch after loading version 3.0:http://swiki.gsug.org:8080/sqfixes/2274.html.
• Apply this version 3.0.2 patch to allow the plugin to build cleanly on the latest VM source code from Ian and from the SourceForge site:http://swiki.gsug.org:8080/sqfixes/2477.html.
• Apply this version 3.0.3 patch to fix an error in the Win32 plugin (thanks to Anthony Hannan for this fix)http://swiki.gsug.org:8080/sqfixes/2838.html.
• Apply this version 3.0.4 patch if you are usingIOHandlewith OSProcess:http://swiki.gsug.org:8080/sqfixes/2850.html.
• Version 3.0.5 is a patch which adds features to the Unix plugin to support event forwarding:http://swiki.gsug.org:8080/sqfixes/3001.html. This will be used by an upcoming release of OSProcess, but you do not need it now unless you are building and distributing the plugin for Unix users.
• Version 3.0.6 fixes an OSPP bug introduced in 3.0.5, and contains updates for SqueakMap and Squeak 3.6:http://swiki.gsug.org:8080/sqfixes/4015.html.
• Windows users can download this precompiled dll:Win32OSProcessPlugin.ziporWin32OSProcessPlugin.dll.gz. This is the dll which was included with the 3.0.3 patch. If you download the gzipped version, make sure it is named "Win32OSProcessPlugin.dll.gz" on your local system. The Swiki file versioning may cause it to be named something else.

• http://swiki.gsug.org:8080/sqfixes/2065.html.

• http://swiki.gsug.org:8080/sqfixes/1992.html- 2.6.1 patchhttp://swiki.gsug.org:8080/sqfixes/2003.html.

• http://swiki.gsug.org:8080/sqfixes/1950.html.

• http://swiki.gsug.org:8080/sqfixes/1881.html.

• http://swiki.gsug.org:8080/sqfixes/1620.html.

• OSProcessV2-2.cs.gz.

• http://swiki.gsug.org:8080/sqfixes/1550.html.

• Readme-OSProcessV2-0.cs.gz-UnixOSProcessPlugin.c.gz

• ExternalUnixProcess now has interesting instance variables, and knows how to execute commands in an external shell.
• ConnectedUnixProcess provides IO to child processes (such as shells) from Squeak, and provides a framework for command pipelines.
• Shell implements a basic command shell in Smalltalk, with file name globbing and other basics to eliminate the need for /bin/sh.
• Merged functionality of ShellProxy into ConnectedUnixProcess. Eliminated ShellProxy.
• Better implementation of UnixProcess class>makeVmIn: with error output of the Unix make returned to Squeak. Convenient for building plugins or new VMs without ever leaving Squeak. Be sure to check outVMMakerbyTim Rowledgealso.
• Changed UnixOSProcessPlugin to close all unneeded file handles (including sockets) prior in a child process. This eliminates some flakey behavior in child processes connected to Squeak by pipes, which failed to exit at expected times due to the old file descriptors remaining open. The #primitiveForkAndExecClosingAll method replaces the previous #primitiveForkAndExec for this. An attempt is made to maintain backward compatibility for images running on a VM with the old plugin.
• Improved handling of death of child. Added sigchld and sigpipe restore for child in a fork(). Cleaned up the sigpipe handler.
• Refactored and improved use of OSPipe.
• IOHandle (dtl) andVMMaker(tpr) supported but not required.
• Last but not least: The verbosity of Squeak and the complexity of Unix, all in one hard to use package. Amaze your friends and confound your enemies by evaluating incomprehensible expressions like this: "((Shell command: 'ps') | 'grep squeak' | 'cut -c16-100') output"

• Updated support for IOHandle.
• General cleanup of UnixOSProcessAccessor and UnixOSProcessPlugin.
• Cleaned up #update: in UnixProcess. - UnixOSProcessAccessor now adds itself to the system startup list, and properly notifies its dependents following an image restart (distinguishes between a cold start and an image save so that UnixProcess can decide what to do with its child process dictionary).
• Subclassed OSProcessAccessor from Model rather than Object.

• Split UnixOSProcessAccessor into two classes. UnixOSProcessPlugin now contains the methods which can be translated to a C plugin library, and UnixOSProcessAccessor no longer contains the plugin code. Cleaned up some of the plugin code to minimize C compiler warnings for strict compilers.
• Added various improvements to child process handling, particularly across image restarts. Added a primitive to UnixOSProcessPlugin to allow Squeak to check if a child process still exists following an image restart. ExternalOSProcess proxies now do a better job of keeping track of the external OS processes which they represent.
• Added UnixProcess class>makeVM utility for rebuilding the VM from a running Squeak session.