sRead (Function)

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Various
Transmission between two computers that use character strings in different formats (UNICODE and ANSI)
Using an external library: RXTX

WINDEV

WEBDEV

WINDEV Mobile

Others

See also

sRead (Function)

In french: sLit

Reads a character string in the entry buffer of the specified serial port. The port must be opened beforehand (sOpen).

Reads a buffer in the entry buffer of the specified serial port or infrared port. The port must be opened beforehand (sOpen).

Remarks:

This function cannot be used with a parallel port.
This function affects the server.
Versions 16 and later
Infrared ports are not managed.
New in version 16
Infrared ports are not managed.
Infrared ports are not managed.
Versions 25 and later
Only serial ports are managed.
New in version 25
Only serial ports are managed.
Only serial ports are managed.

Versions 16 and later

This function is now available for the Java applications.

New in version 16

This function is now available for the Java applications.

Versions 25 and later

This function is now available for WEBDEV sites in Linux.

This function is now available for WINDEV applications in Linux.

New in version 25

This function is now available for WEBDEV sites in Linux.

This function is now available for WINDEV applications in Linux.

This function is now available for WEBDEV sites in Linux.

This function is now available for WINDEV applications in Linux.

Example

// Read 20 characters in the Message variable from
// the entry buffer of COM1
Msg is string
Msg = sRead(1, 20)

// Read 20 bytes in the Message variable from the entry buffer of COM1
Msg is Buffer
Msg = sRead(1, 20)

Syntax

Reading a number of bytes and retrieving a string Hide the details

<Result> = sRead(<Port number> , <Number of bytes to read>)

<Result>: Character string

Character string read in the entry buffer,
0 if the read operation was not performed.

<Port number>: Integer

Number of the relevant serial port: 1, 2, 3, ... 32 for COM1, COM2, COM3, ... COM32.
Identifier of the serial port returned by sOpen (if this function was called with a serial port name).
Versions 25 and later
Only this type of parameter is available.
New in version 25
Only this type of parameter is available.
Only this type of parameter is available.

<Number of bytes to read>: Integer

Number of bytes to read in the entry buffer of the serial port. The number of bytes to read is returned by sInEntryQueue.

Reading a number of bytes and retrieving a buffer Hide the details

<Result> = sRead(<Port number> , <Size to Read>)

<Result>: Buffer

Buffer read in the entry buffer,
0 if the read operation was not performed.

<Port number>: Integer

Relevant port number:
Number of serial port: 1, 2, 3, ... 32 for COM1, COM2, COM3, ... COM32.
Number of infrared port: 1, 2, 3, ... 32 for IR1, IR2, IR3, ... IR32.
Port number returned by sOpen (if this function was called with a port name).

<Size to Read>: Integer

Number of bytes to read in the entry buffer of the serial port. The number of bytes to read is returned by sInEntryQueue.
Reminder: In UNICODE, each character occupies two memory bytes.

Remarks

Various

sRead has no effect if the port was not opened by sOpen.
sRead clears the input queue from the number of bytes actually read.
A 32-bit application is locked during the duration of the transfer. To avoid this lock, the time-out between two read operations must be specified in sOpen. Once the time-out is over and if the read operation was not performed, sRead returns 0.
WLanguage does not allow you to manage the control signals.

Transmission between two computers that use character strings in different formats (UNICODE and ANSI)

Some conversions are required to perform a transmission between two computers that use different formats of character strings (Windows (ANSI) and Windows Mobile (UNICODE) for example):


Format of character strings on the current computer	Write operation (sWrite)	Read operation (sRead)
Format of character strings on the current computer	Write operation (sWrite)	Buffer containing a string in ANSI format	Buffer containing a string in UNICODE format
ANSI (PC running Windows XP for example)	The character string will be in ANSI format	No conversion is required	Conversion required (UnicodeToAnsi)
UNICODE (Pocket PC running Windows CE for example)	The character string will be in UNICODE format	Conversion required (AnsiToUnicode)	No conversion is required

Versions 16 and later

Using an external library: RXTX

In Java, the use of functions for handling the serial and parallel ports (sOpen, sWrite, sRead, ...) requires the presence of an external library: RXTX.

This library includes a Jar archive and one or more native libraries that depend on the operating system on which the application is run. To use these functions:

the Jar archive (RXTXComm.jar) must:
- be found in the same directory as the Java application generated by WINDEV,
- be found in the execution classpath of the application,
- be directly included in the generated application (from the wizard for Java generation).
the native libraries corresponding to the operating system on which the application is run must be found:
- in the same directory as the Java application generated by WINDEV,
- in the path of the application libraries (librarypath).

The RXTX library and its documentation can be downloaded from: http://users.frii.com/jarvi/rxtx/index.html (link valid at the time this documentation was published).

Caution: The management of infrared ports is not available in Java.

New in version 16

Using an external library: RXTX

In Java, the use of functions for handling the serial and parallel ports (sOpen, sWrite, sRead, ...) requires the presence of an external library: RXTX.

This library includes a Jar archive and one or more native libraries that depend on the operating system on which the application is run. To use these functions:

the Jar archive (RXTXComm.jar) must:
- be found in the same directory as the Java application generated by WINDEV,
- be found in the execution classpath of the application,
- be directly included in the generated application (from the wizard for Java generation).
the native libraries corresponding to the operating system on which the application is run must be found:
- in the same directory as the Java application generated by WINDEV,
- in the path of the application libraries (librarypath).

The RXTX library and its documentation can be downloaded from: http://users.frii.com/jarvi/rxtx/index.html (link valid at the time this documentation was published).

Caution: The management of infrared ports is not available in Java.

Using an external library: RXTX

In Java, the use of functions for handling the serial and parallel ports (sOpen, sWrite, sRead, ...) requires the presence of an external library: RXTX.

This library includes a Jar archive and one or more native libraries that depend on the operating system on which the application is run. To use these functions:

the Jar archive (RXTXComm.jar) must:
- be found in the same directory as the Java application generated by WINDEV,
- be found in the execution classpath of the application,
- be directly included in the generated application (from the wizard for Java generation).
the native libraries corresponding to the operating system on which the application is run must be found:
- in the same directory as the Java application generated by WINDEV,
- in the path of the application libraries (librarypath).

The RXTX library and its documentation can be downloaded from: http://users.frii.com/jarvi/rxtx/index.html (link valid at the time this documentation was published).

Caution: The management of infrared ports is not available in Java.

Business / UI classification : Business Logic

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