12.2: File Write
- Page ID
- 54325
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The file must be opened for “write” or “readwrite” access before any information can be written to the file. The general form of the write statement is as follows:
write (unit=<unit number>, fmt=<format statement>, &
advance="no", iostat=<variable>) &
<variables/expressions>
The write statement is the same as the simple write; however, the unit number must be the number assigned during the open operation. Normally, the next write will be on the next line. The advance="no" is optional. If it is included, the next write will be on the same line where the previous line stopped.
For example to open a file named temp.txt and place the string “Fortran Example” and the numbers 42, and 3.14159 on separate lines, the following declarations:
integer :: myanswer=42, myopenstatus, mywritestatus real, parameter :: pi=3.14159 character(15) :: mymessage="Fortran Example" character(8) :: myfilename="temp.txt"
and the following Fortran statements,
open (unit=10, file=myfilename, status="replace", &
action="write", position="rewind", &
iostat=myopenstatus)
if (myopenstatus > 0) stop "Cannot open file."
write (10, '(a/, i5/, f7.5)', iostat=mywritestatus) &
mymessage, myanswer, pi
would write the file information to the file.