VMS Help PASCAL, Input Output, Seq Access Input, RESET *Conan The Librarian (sorry for the slow response - running on an old VAX) |
The RESET procedure readies a file for reading. Syntax: RESET( file_variable [[, file_name]] [[, ERROR := error-recovery]] ); The 'file_variable' is the name of the file variable associated with the input file. You do not need this argument if the file was opened with the OPEN procedure. The 'file_name' represents the string expression to be associated with the 'file_variable'. If the file was previously opened with the OPEN procedure, 'file_name' is ignored. The 'error-recovery' represents 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. The file can be in any mode before you call RESET; a call to RESET sets the file to inspection mode. If the file is an external file and is not already open, RESET opens it using the same defaults as the OPEN procedure. You cannot use RESET to create a file. After execution of RESET, the file is positioned at the first component, and the file buffer variable contains the value of this component. If the file is not empty, EOF and UFB return FALSE and the first component is locked to prevent access by other processes. If the file is empty, EOF and UFB return TRUE. If the file does not exist, RESET does not create it, but returns an error at run time. You should call RESET before reading any file with sequential organization except the predeclared file INPUT. The RESET procedure removes the end-of-file marker from any file connected to a terminal device (including INPUT), thus allowing reading from the file to continue. If you call RESET for the predeclared file OUTPUT, an error occurs. A call to RESET on a relative file opened for direct access positions the file at its first existing component. A call to RESET on an indexed file opened for keyed access positions the file at the first component relative to the primary key. See the "Compaq Pascal Language Reference Manual" for a complete description of the RESET procedure.
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