Полезная информация


NAME

getcwd - get pathname of current working directory


SYNOPSIS

    use Cwd;
    $dir = cwd;

    use Cwd;
    $dir = getcwd;

    use Cwd;
    $dir = fastgetcwd;

    use Cwd 'chdir';
    chdir "/tmp";
    print $ENV{'PWD'};

    use Cwd 'abs_path';
    print abs_path($ENV{'PWD'});

    use Cwd 'fast_abs_path';
    print fast_abs_path($ENV{'PWD'});


DESCRIPTION

The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions in Perl.

The abs_path() function takes a single argument and returns the absolute pathname for that argument. It uses the same algoritm as getcwd(). (actually getcwd() is abs_path(``.''))

The fastcwd() function looks the same as getcwd(), but runs faster. It's also more dangerous because it might conceivably chdir() you out of a directory that it can't chdir() you back into. If fastcwd encounters a problem it will return undef but will probably leave you in a different directory. For a measure of extra security, if everything appears to have worked, the fastcwd() function will check that it leaves you in the same directory that it started in. If it has changed it will die with the message ``Unstable directory path, current directory changed unexpectedly''. That should never happen.

The fast_abs_path() function looks the same as abs_path(), but runs faster. And like fastcwd() is more dangerous.

The cwd() function looks the same as getcwd and fastgetcwd but is implemented using the most natural and safe form for the current architecture. For most systems it is identical to `pwd` (but without the trailing line terminator).

It is recommended that cwd (or another *cwd() function) is used in all code to ensure portability.

If you ask to override your chdir() built-in function, then your PWD environment variable will be kept up to date. (See Overriding Builtin Functions.) Note that it will only be kept up to date if all packages which use chdir import it from Cwd.


DISCLAIMER

We are painfully aware that these documents may contain incorrect links and misformatted HTML. Such bugs lie in the automatic translation process that automatically created the hundreds and hundreds of separate documents that you find here. Please do not report link or formatting bugs, because we cannot fix per-document problems. The only bug reports that will help us are those that supply working patches to the installhtml or pod2html programs, or to the Pod::HTML module itself, for which I and the entire Perl community will shower you with thanks and praises.

If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.

--Tom Christiansen, Perl Documentation Compiler and Editor


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