 |
<Files> |
[
open |
close |
fileerror |
print |
println |
scan |
scanln |
eof
]
The values of the file type are file handles with only a
limited number of operations.
Opening and closing files
- exp ::= open ( exp )
exp ::= open ( exp , exp )
- The first argument is a string designating a file on the server's
file system. The second argument specifies the open mode and must be
on of the strings "read", "write", or
"append", defaulting to "read" if not present. The
path is the
$SERVICEDIR/<<service-name>>.
- exp ::= close (
exp )
- Will close the file associated with the file handle given as
argument. The expression will return void.
- exp ::= fileerror (
exp )
- Takes an expression of type file and returns a boolean
that is true if a previous open on the
file was unsuccessful or an error has previously occurred
reading from or writing to the file. Otherwise it return
false.
Printing in files
- exp ::= print ( exp , exp )
- The string specified in the second argument is printed to the file
designated by the first argument. The file must be in either write or
append mode. The expression will return void.
- exp ::= println (
exp , exp )
- The string specified in the second argument plus a newline
character is printed to the file designated by the first argument.
The file must be in either write or append mode. The expression will
return void.
Scanning in files
- exp ::= scan (
exp , id )
- Scan will take two arguments, a file handle and a format. It will scan as much of the file from
the current file position that is in the regular language defined by
the format and advance the file pointer accordingly. The file must be
in read mode. The expression will return what was scanned from the
file.
- exp ::= scanln ( exp )
- Scans and returns one line from the file specified in the
argument. After this, the file pointer is advanced accordingly. The
file must be in read mode.
- exp ::= eof ( exp )
- Returns a true if the file designated by the argument is at
the end-of-file mark, false if not. The file must be in read
mode.
