06-17-2012
It seems to me any solution should always make use a temporary intermediate file for safety reasons. If we read the whole file into memory and then write it back to the same file, we run the risk of losing the original in case of power failure during the write-back phase..
With a temporary file there is only mv involved, which is only a rename if the temporary file is in the same dir on the same file system, so a temporary file in the same directory instead of /tmp for example may be preferably. If we use /tmp for example for the intermediate file, a temporary rename to .bak of the original until the move from /tmp may be required and safest will probably be to keep the .bak until the user deletes it..
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LEARN ABOUT DEBIAN
arch::tempfiles
Arch::TempFiles(3pm) User Contributed Perl Documentation Arch::TempFiles(3pm)
NAME
Arch::TempFiles - help to manage temporary files/dirs
SYNOPSIS
use Arch::TempFiles qw(temp_file_name temp_file temp_dir);
# all will be removed automatically on the script completion
my $file_name1 = temp_file();
my $file_name2 = temp_file_name("status");
my $dir_name = temp_dir("arch-tree");
use Arch::TempFiles;
my $tmp = new Arch::TempFiles;
$tmp->root($tmp->dir);
my $file_name = $tmp->name;
open OUT, ">$file_name";
close OUT;
DESCRIPTION
This module deals with temporary file names. It is similar to File::Temp, but simplier and more focused. Also, File::Temp is relatively new
and was not shipped with older perl versions.
Both function interface and object oriented interface are supported.
FUNCTIONS
/METHODS
The following functions are available:
temp_root, temp_name, temp_file_name, temp_dir_name, temp_file, temp_dir.
The corresponding class methods are available too:
root, name, file_name, dir_name, file, dir.
temp_root [dir]
$tmp->root [dir]
Change or return the root of the temporary files and dirs. The default is either $ENV{TMP_DIR} or "/tmp".
temp_name [label]
$tmp->name [label]
Return the unused temporary file name. The default file name is "/tmp/,,arch-XXXXXX" where XXXXXX is a random number. To change this
name use "temp_root" and/or provide label that replaces "arch".
Please note, that the operation of acquiring the file name using this function/method and actual creating of this file is not atomic.
So you may need to call this method again if the creation is failed, for example if some other process created the same file in the
middle.
temp_file_name [label]
$tmp->file_name [label]
Like "temp_name", but stores the name in the file list that will be removed on the end (on object destruction).
temp_dir_name [label]
$tmp->dir_name [label]
Like "temp_name", but stores the name in the dir list that will be removed on the end (on object destruction).
temp_file [label]
$tmp->file [label]
Like "temp_file_name", but also creates the file.
temp_dir [label]
$tmp->dir [label]
Like "temp_dir_name", but also creates the dir.
BUGS
Awaiting for your reports.
AUTHORS
Mikhael Goikhman (migo@homemail.com--Perl-GPL/arch-perl--devel).
SEE ALSO
For a different interface, see File::Temp.
perl v5.10.1 2005-04-22 Arch::TempFiles(3pm)