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}</lang>
The File is managed by reference count, and it gets closed when it gets out of scope or it changes. The 'line' is a char[] (with newline), so if you need a string you have to idup it.
=={{header|Perl}}==
For the simple case of iterating over the lines of a file you can do:
<lang perl>open(FOO, '<', 'foobar.txt') or die $!;
while (<FOO>) { # each line is stored in $_, with terminating newline
chomp; # chomp, short for chomp($_), removes the terminating newline
process($_);
}
close(FOO);</lang>
The angle bracket operator <code>< ></code> reads a filehandle line by line. (The angle bracket operator can also be used to open and read from files that match a specific pattern, by putting the pattern in the brackets.)
Without specifying the variable that each line should be put into, it automatically puts it into <code>$_</code>, which is also conveniently the default argument for many Perl functions. If you wanted to use your own variable, you can do something like this:
<lang perl>open(FOO, '<', 'foobar.txt') or die $!;
while (my $line = <FOO>) {
chomp($line);
process($_);
}
close(FOO);</lang>
The special use of the angle bracket operator with nothing inside, will read from all files whose names were specified on the command line:
<lang perl>while (<>) {
chomp;
process($_);
}</lang>
=={{header|Python}}==
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for line in f:
process(line)</lang>
The with statement ensures the correct closing of the file after it is
Python also has the [http://docs.python.org/library/fileinput.html fileinput module]. This can process multiple files parsed from the command line and can be set to modify files 'in-place'.
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