Whats is the difference between Unix and Linux

[LilTCLer]

when developing and executing between Unix and Linux. I have a script that works perfectly in Unix, and after changing "#!/usr/local/bin/expect" to "#!/usr/bin/expect" the script is not working correctly. Are there major difference between Unix and Linux expect that I'm just not aware of?

The script I'm testing is pretty simple and shouldn't be platform dependent.

 

[Bong]

Well, the obvious question is whether the Expect executable actually is in /usr/bin.

I have experienced no differences (with Tcl) on Unix and Linux.

_________________
Bob Rashkin

 

[LilTCLer]

That is why I have changed the re-director to #!/usr/bin/expect since that is where it is installed on the Linux machine.

 

[LilTCLer]

For example, a super simple script that is not working correctly:

#!/usr/bin/expect

puts "Enter your name"
sleep 5
set name [ gets stdin ]
puts "Hello $name"

Here is what I get a runtime:

[root@localhost david]# expect test
Enter your name
Hello
[root@localhost david]#

It doesn't allow the script to read from STDIN.

 

[Bong]

It sounds like there's a problem with the Tcl installation. Have you tried Tcl_CreateChannel?

_________________
Bob Rashkin

 

[LilTCLer]

I'm not familiar with that command. Can you fill me in on what it is/does?

 

[Bong]

Well, I'm not familiar with it either. I just found it on the help file:

DESCRIPTION
Tcl uses a two-layered channel architecture. It provides a generic upper layer to enable C and Tcl programs to perform input and output using the same APIs for a variety of files, devices, sockets etc. The generic C APIs are described in the manual entry for Tcl_OpenFileChannel.

The lower layer provides type-specific channel drivers for each type of device supported on each platform. This manual entry describes the C APIs used to communicate between the generic layer and the type-specific channel drivers. It also explains how new types of channels can be added by providing new channel drivers.

Channel drivers consist of a number of components: First, each channel driver provides a Tcl_ChannelType structure containing pointers to functions implementing the various operations used by the generic layer to communicate with the channel driver. The Tcl_ChannelType structure and the functions referenced by it are described in the section TCL_CHANNELTYPE, below.

Second, channel drivers usually provide a Tcl command to create instances of that type of channel. For example, the Tcl open command creates channels that use the file and command channel drivers, and the Tcl socket command creates channels that use TCP sockets for network communication.

Third, a channel driver optionally provides a C function to open channel instances of that type. For example, Tcl_OpenFileChannel opens a channel that uses the file channel driver, and Tcl_OpenTcpClient opens a channel that uses the TCP network protocol. These creation functions typically use Tcl_CreateChannel internally to open the channel.

To add a new type of channel you must implement a C API or a Tcl command that opens a channel by invoking Tcl_CreateChannel. When your driver calls Tcl_CreateChannel it passes in a Tcl_ChannelType structure describing the driver's I/O procedures. The generic layer will then invoke the functions referenced in that structure to perform operations on the channel.

Tcl_CreateChannel opens a new channel and associates the supplied typePtr and instanceData with it. The channel is opened in the mode indicated by mask. For a discussion of channel drivers, their operations and the Tcl_ChannelType structure, see the section TCL_CHANNELTYPE, below.

Tcl_CreateChannel interacts with the code managing the standard channels. Once a standard channel was initialized either through a call to Tcl_GetStdChannel or a call to Tcl_SetStdChannel closing this standard channel will cause the next call to Tcl_CreateChannel to make the new channel the new standard channel too. See Tcl_StandardChannels for a general treatise about standard channels and the behaviour of the Tcl library with regard to them.

Tcl_GetChannelInstanceData returns the instance data associated with the channel in channel. This is the same as the instanceData argument in the call to Tcl_CreateChannel that created this channel.

Tcl_GetChannelType returns a pointer to the Tcl_ChannelType structure used by the channel in the channel argument. This is the same as the typePtr argument in the call to Tcl_CreateChannel that created this channel.

Tcl_GetChannelName returns a string containing the name associated with the channel, or NULL if the channelName argument to Tcl_CreateChannel was NULL.

Tcl_GetChannelHandle places the OS-specific device handle associated with channel for the given direction in the location specified by handlePtr and returns TCL_OK. If the channel does not have a device handle for the specified direction, then TCL_ERROR is returned instead. Different channel drivers will return different types of handle. Refer to the manual entries for each driver to determine what type of handle is returned.

Tcl_GetChannelThread returns the id of the thread currently managing the specified channel. This allows channel drivers to send their file events to the correct event queue even for a multi-threaded core.

Tcl_GetChannelMode returns an OR-ed combination of TCL_READABLE and TCL_WRITABLE, indicating whether the channel is open for input and output.

Tcl_GetChannelBufferSize returns the size, in bytes, of buffers allocated to store input or output in channel. If the value was not set by a previous call to Tcl_SetChannelBufferSize, described below, then the default value of 4096 is returned.

Tcl_SetChannelBufferSize sets the size, in bytes, of buffers that will be allocated in subsequent operations on the channel to store input or output. The size argument should be between ten and one million, allowing buffers of ten bytes to one million bytes. If size is outside this range, Tcl_SetChannelBufferSize sets the buffer size to 4096.

Tcl_NotifyChannel is called by a channel driver to indicate to the generic layer that the events specified by mask have occurred on the channel. Channel drivers are responsible for invoking this function whenever the channel handlers need to be called for the channel. See WATCHPROC below for more details.

Tcl_BadChannelOption is called from driver specific set or get option procs to generate a complete error message.

Tcl_ChannelBuffered returns the number of bytes of input currently buffered in the internal buffer (push back area) of the channel itself. It does not report about the data in the overall buffers for the stack of channels the supplied channel is part of.

Tcl_IsChannelShared checks the refcount of the specified channel and returns whether the channel was shared among multiple interpreters (result == 1) or not (result == 0).
.... >>>there's lots more

_________________
Bob Rashkin