VMS Help PASCAL, Input Output, Seq Access Input, GET *Conan The Librarian (sorry for the slow response - running on an old VAX) |
The GET procedure advances the file position and reads the next component of the file into the file buffer variable. If the file has relative or indexed organization, the component is also locked to prevent access by other processes. Syntax: GET( file_variable [[,ERROR := error-recovery]] ); The 'file_variable' is the name associated with the input file. The 'error-recovery' specifies the action to be taken if an error occurs during execution of the routine. By default, after the first error, the error message is printed and execution is stopped. Before the GET procedure is used for the first time to read one or more file components, the file must be in inspection mode and prepared for reading input. Depending on the access method specified when the file was opened, you can prepare the file for input in the following ways: o If the file is open for sequential access, call the RESET procedure. RESET sets the mode to inspection, advances the file position to the first component, and assigns the component's value to the file buffer variable. o If the file is open for direct access, call either the RESET or the FIND procedure to position the file. o If the file is open for keyed access, call the FINDK, RESET, or RESETK procedure to position the file. As a result of the GET procedure, the file remains in inspection mode, and the file position advances to the next component. If a component is found other than the end-of-file marker, the component is locked, EOF is set to FALSE, the file buffer variable takes on the value of the component, and UFB is set to FALSE. If a component is not found or the end of the file is reached, EOF and UFB are set to TRUE. If the GET procedure fails, UFB is set to TRUE and EOF becomes undefined. See the "Compaq Pascal Language Reference Manual" for the complete description of the GET procedure.
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