Types of I/O Statements

The table below lists the Intel Fortran I/O statements:

Category and statement name	Description
File connection
OPEN	Connects a unit number with an external file and specifies file connection characteristics.
CLOSE	Disconnects a unit number from an external file.
File inquiry
DEFINE FILE	Specifies file characteristics for a direct access relative file and connects the unit number to the file, similar to an OPEN statement. Provided for compatibility with compilers older than FORTRAN-77.
INQUIRE	Returns information about a named file, a connection to a unit, or the length of an output item list.
Record position
BACKSPACE	Moves the record position to the beginning of the previous record (sequential access only).
DELETE	Marks the record at the current record position in a relative file as deleted (direct access only).
ENDFILE	Writes an end-of-file marker after the current record (sequential access only).
FIND	Changes the record position in a direct access file. Provided for compatibility with compilers older than FORTRAN-77.
REWIND	Sets the record position to the beginning of the file (sequential access only).
Record input
READ	Transfers data from an external file record or an internal file to internal storage.
ACCEPT	Reads input from stdin. Unlike READ, ACCEPT only provides formatted sequential input and does not specify a unit number.
Record output
WRITE	Transfers data from internal storage to an external file record or to an internal file.
REWRITE	Transfers data from internal storage to an external file record at the current record position (direct access relative files only).
TYPE	Writes record output to stdout.
PRINT	Transfers data from internal storage to stdout. Unlike WRITE, PRINT only provides formatted sequential output and does not specify a unit number.
FLUSH	Flushes the contents of an external unit's buffer to its associated file.

In addition to the READ, WRITE, REWRITE, TYPE, and PRINT statements, other I/O record-related statements are limited to a specific file organization. For instance:

The DELETE statement only applies to relative files. (Detecting deleted records is only available if the vms option was specified when the program was compiled.)
The BACKSPACE statement only applies to sequential files open for sequential access.
The REWIND statement only applies to sequential files open for sequential access and to direct access files.
The ENDFILE statement only applies to certain types of sequential files open for sequential access and to direct access files.

The file-related statements (OPEN, INQUIRE, and CLOSE) apply to any relative or sequential file.