VMS Help READ, Examples *Conan The Librarian (sorry for the slow response - running on an old VAX) |
1.$ OPEN IN NAMES.DAT $ LOOP: $ READ/END_OF_FILE=ENDIT IN NAME . . . $ GOTO LOOP $ ENDIT: $ CLOSE IN The OPEN command opens the file NAMES.DAT for input and assigns it the logical name of IN. The READ command reads records from the file IN and places the contents into the symbol NAME. The READ command specifies the label ENDIT to receive control when the last record in the file has been read. The procedure loops until all records in the file have been processed. 2.$ READ/ERROR=READERR/END_OF_FILE=OKAY MSGFILE CODE . . . $ READERR: $ CLOSE MSGFILE . . . $ OKAY: $ CLOSE MSGFILE $ EXIT The READ command reads records from the file MSGFILE and places the contents into the symbol CODE. The READ command also uses the /ERROR and /END_OF_FILE qualifiers to specify labels to receive control at the end-of-file (EOF) and on error conditions. At the EOF, control is transferred to the label OKAY. On other read errors, control is transferred to the READERR label. 3.$ READ SYS$COMMAND DATA_LINE $ WRITE OUTPUT_FILE DATA_LINE . . . The READ command requests data from the current SYS$COMMAND device. If the command procedure containing these lines is executed interactively, the command issues a prompt to the terminal, accepts a line of data, and equates the data entered to the symbol name DATA_LINE. Then the WRITE command writes the value of the symbol DATA_LINE to the file identified by the logical name OUTPUT_FILE. 4.$ OPEN/READ INPUT_FILE TRNTO::INVENTORY.DAT $ OPEN/APPEND OUTPUT_FILE RECEIVE.DAT $ READ INPUT_FILE DATA_LINE $ WRITE OUTPUT_FILE DATA_LINE The OPEN/READ command opens the file INVENTORY.DAT at the remote node TRNTO for reading and assigns it the logical name INPUT_FILE. The OPEN/APPEND command opens the file RECEIVE.DAT in the current default directory. The READ command requests data from the file INVENTORY.DAT at the remote node TRNTO. The WRITE command writes the value of the symbol DATA_LINE to the end of the local file RECEIVE.DAT.
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