03-24-2008
Access()System call
Hi,
Is it possible to check the Existence/read/write of stdin,stdout,stderr using access() call like for the files we do.
Ex: fd=access("./hi.txt",F_OK)
Similarly I wanna check stdin/tdout/stderr using access() call
I tried using fd=access(stdout,F_OK);
But the result is -1.
I believe I did some error in writing it. Will you please suggest the correct way?
Also one more doubt with access() call. Is it True that the standard file desc of STDIN,STDOUT and STDERR are 0,1,2 respectively?
Thanks,
Ramkrix
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LEARN ABOUT DEBIAN
gnupg::handles
GnuPG::Handles(3pm) User Contributed Perl Documentation GnuPG::Handles(3pm)
NAME
GnuPG::Handles - GnuPG handles bundle
SYNOPSIS
use IO::Handle;
my ( $stdin, $stdout, $stderr,
$status_fh, $logger_fh, $passphrase_fh,
)
= ( IO::Handle->new(), IO::Handle->new(), IO::Handle->new(),
IO::Handle->new(), IO::Handle->new(), IO::Handle->new(),
);
my $handles = GnuPG::Handles->new
( stdin => $stdin,
stdout => $stdout,
stderr => $stderr,
status => $status_fh,
logger => $logger_fh,
passphrase => $passphrase_fh,
);
DESCRIPTION
GnuPG::Handles objects are generally instantiated to be used in conjunction with methods of objects of the class GnuPG::Interface.
GnuPG::Handles objects represent a collection of handles that are used to communicate with GnuPG.
OBJECT METHODS
Initialization Methods
new( %initialization_args )
This methods creates a new object. The optional arguments are initialization of data members.
hash_init( %args ).
OBJECT DATA MEMBERS
stdin
This handle is connected to the standard input of a GnuPG process.
stdout
This handle is connected to the standard output of a GnuPG process.
stderr
This handle is connected to the standard error of a GnuPG process.
status
This handle is connected to the status output handle of a GnuPG process.
logger
This handle is connected to the logger output handle of a GnuPG process.
passphrase
This handle is connected to the passphrase input handle of a GnuPG process.
command
This handle is connected to the command input handle of a GnuPG process.
options
This is a hash of hashrefs of settings pertaining to the handles in this object. The outer-level hash is keyed by the names of the
handle the setting is for, while the inner is keyed by the setting being referenced. For example, to set the setting "direct" to true
for the filehandle "stdin", the following code will do:
# assuming $handles is an already-created
# GnuPG::Handles object, this sets all
# options for the filehandle stdin in one blow,
# clearing out all others
$handles->options( 'stdin', { direct => 1 } );
# this is useful to just make one change
# to the set of options for a handle
$handles->options( 'stdin' )->{direct} = 1;
# and to get the setting...
$setting = $handles->options( 'stdin' )->{direct};
# and to clear the settings for stdin
$handles->options( 'stdin', {} );
The currently-used settings are as follows:
direct
If the setting "direct" is true for a handle, the GnuPG process spawned will access the handle directly. This is useful for having
the GnuPG process read or write directly to or from an already-opened file.
SEE ALSO
GnuPG::Interface,
perl v5.12.4 2009-04-21 GnuPG::Handles(3pm)