When you try to open a nonexistent file in output or append mode, the file is created automatically. When you try to open a file for sequential input, the file must already exist. See MIME charset names for a list of valid MIME charset values. The default is the platform-native character set, except that if a UTF-16 or UTF-8 byte order mark (BOM) is present, the BOM character set is used, and on OS/400 the CCSID is used if a BOM is not present. MIMECharsetName designates the character set. The default buffer size for sequential files is 512 bytes. However, larger buffer sizes require more memory. This is a performance-enhancing feature: the larger the buffer, the faster the I/O. To get an unused fileNumber, use the FreeFile function.īufferSize is the number of characters loaded into the internal buffer before being flushed to disk. Access in all three sequential modes is one line at a time. Where Input means read-only access to the file, Output means write-only access, and Append means write-only access starting at the end of the file. After opening a file, you must close it before opening it in another mode. However, a sequential file is not well suited for binary data, because a number in a sequential file is written as a character string.Ī sequential file can be opened in one of three modes: input, output, or append.
#Sequential characters series
Sequential files provide access at the level of lines or strings of text: that is, data that is not divided into a series of records. By default this is the platform-native character set. The character is in the character set specified when the file is opened. Each character in the file is assumed to be either a text character or some other ASCII control character such as newline.
A sequential file is an ordinary text file.
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