file handling - Difference between '>>' and '>' in Perl

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Learn more about Teams Also note that the 3-argument form of open, along with the use of lexical file handles, is generally recommended. In other words, use a scalar variable, rather than something like


    MYFILE

, for your file handle. For example:


    open(my $file_handle, '>', 'output.txt') or die $!

. – FMc Jun 9, 2010 at 11:23

open (MYFILE, '>>data.txt') — Open


    data.txt

, keep the original data, append data from the end.

open (MYFILE, '>data.txt') — Open


    data.txt

, delete everything inside, and write data from the start.

If MODE is '<' or nothing, the file is opened for input. If MODE is '>' , the file is truncated and opened for output, being created if necessary. If MODE is '>>' , the file is opened for appending, again being created if necessary.

It stems from the shell usage that,


    cmd < file.txt

to copy file into stdin,


    cmd > file.txt

to write stdout into a file, and


    cmd >> file.txt

to append stdout to the end of the file.

@mirod:


    open(MYFILE, '>data.txt')

is equivalent to


    open(MYFILE, '>', 'data.txt')

. Please read the link. – kennytm Jun 9, 2010 at 9:26

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