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NAME

Prima::Utils - miscellanneous routines

DESCRIPTION

The module contains miscellaneous helper routines.

API

alarm $TIMEOUT, $SUB, @PARAMS

Calls SUB with PARAMS after TIMEOUT milliseconds.

beep [ FLAGS = mb::Error ]

Invokes the system-depended sound and/or visual bell, corresponding to one of following constants:

        mb::Error
        mb::Warning
        mb::Information
        mb::Question
get_gui

Returns one of gui::XXX constants, reflecting the graphic user interface used in the system:

        gui::Default
        gui::PM
        gui::Windows
        gui::XLib
        gui::GTK
get_os

Returns one of apc::XXX constants, reflecting the platfrom. Currently, the list of the supported platforms is:

        apc::Win32
        apc::Unix
ceil DOUBLE

Obsolete function.

Returns stdlib's ceil() of DOUBLE

find_image PATH

Converts PATH from perl module notation into a file path, and searches for the file in @INC paths set. If a file is found, its full filename is returned; otherwise undef is returned.

floor DOUBLE

Obsolete function.

Returns stdlib's floor() of DOUBLE

last_error

Returns last system error, if any

path [ FILE ]

If called with no parameters, returns path to a directory, usually ~/.prima, that can be used to contain the user settings of a toolkit module or a program. If FILE is specified, appends it to the path and returns the full file name. In the latter case the path is automatically created by File::Path::mkpath unless it already exists.

post $SUB, @PARAMS

Postpones a call to SUB with PARAMS until the next event loop tick.

query_drives_map [ FIRST_DRIVE = "A:" ]

Returns anonymous array to drive letters, used by the system. FIRST_DRIVE can be set to other value to start enumeration from. Win32 can probe removable drives there, so to increase responsiveness of the function it might be reasonable to call it with FIRST_DRIVE set to C: .

If the system supports no drive letters, empty array reference is returned ( unix ).

query_drive_type DRIVE

Returns one of dt::XXX constants, describing the type of drive, where DRIVE is a 1-character string. If there is no such drive, or the system supports no drive letters ( unix ), dt::None is returned.

        dt::None
        dt::Unknown
        dt::Floppy
        dt::HDD
        dt::Network
        dt::CDROM
        dt::Memory
sound [ FREQUENCY = 2000, DURATION = 100 ]

Issues a tone of FREQUENCY in Hz with DURATION in milliseconds.

username

Returns the login name of the user. Sometimes is preferred to the perl-provided getlogin ( see "getlogin" in perlfunc ) .

xcolor COLOR

Accepts COLOR string on one of the three formats:

        #rgb
        #rrggbb
        #rrrgggbbb

and returns 24-bit RGB integer value.

Unicode-aware filesystem functions

Since perl win32 unicode support for files is unexistent, Prima has its own parallel set of functions mimicking native functions, ie open, chdir etc. This means that files with names that cannot be converted to ANSI (ie user-preferred) codepage are not visible in perl, but the functions below mitigate that problem.

The following fine points need to be understood prior to using these functions though:

  • Prima makes a distinction whether scalars have their utf8 bit set or not throughout the whole toolking. For example, text output in both unix and windows is different depending on the bit, treating non-utf8-bit text as locale-specific, and utf8-bit text as unicode. The same model is applied for the file systems.

  • Perl implementation for native Win32 creates virtual environments for each thread, keeping current directory, environment variables, etc. This means that under Win32 calling Prima::Utils::chdir will NOT automatically make CORE::chdir assume that value, even if the path is convertable to ANSI. Keep that in mind when mixing Prima and core functions. (To add more confusion, under the unix these two chdirs are identical when the path is fully convertable).

  • Under unix, reading entries from environment or file system is opportunistic: if is a valid utf8, then it is a utf8 string. Mostly because .UTF-8 locale are default and standard everywhere. Prima ignores $ENV{LANG} here. This is a bit problematic on Perls under 5.22 as these don't provide means to check for utf8 string validity, so everything will be slapped a utf8 bit on here -- Beware.

  • Setting environment variables may or may not sync with %ENV , depending on how perl is built. Also, %ENV will warn when trying to set scalars with utf-8 bit there.

access PATH, MODE

Same as POSIX::access.

chdir DIR

Same as CORE::chdir but disregards thread local environment on Win32.

chmod PATH, MODE

Same as CORE::chmod

closedir, readdir, rewinddir, seekdir, telldir DIRHANDLE

Mimic homonymous perl functions

getcwd

Same as Cwd::getcwd

getdir PATH

Reads content of PATH directory and returns array of string pairs, where the first item is a file name, and the second is a file type.

The file type is a string, one of the following:

        "fifo" - named pipe
        "chr"  - character special file
        "dir"  - directory
        "blk"  - block special file
        "reg"  - regular file
        "lnk"  - symbolic link
        "sock" - socket
        "wht"  - whiteout

This function was implemented for faster directory reading, to avoid successive call of stat for every file.

Also, getdir is consistently inclined to treat filenames in utf8, disregarding both perl unicode settings and the locale.

getenv NAME

Reads directly from environment, possibly bypassing %ENV , and disregarding thread local environment on Win32.

Same as CORE::link.

local2sv TEXT

Converts 8-bit text into either 8-bit non-utf8-bit or unicode utf8-bit string. May return undef on memory allocation failure.

mkdir DIR, [ MODE = 0666 ]

Same as CORE::mkdir.

open_file PATH, FLAGS

Same as POSIX::open

open_dir PATH

Returns directory handle to be used on readdir, closedir, rewinddir, telldir, seekdir.

rename OLDNAME, NEWNAME

Same as CORE::rename

rmdir PATH

Same as CORE::rmdir

setenv NAME, VAL

Directly sets environment variable, possibly bypassing %ENV , depending on how perl is built. Also disregards thread local environment on Win32.

Note that effective synchronization between this call and %ENV is not always possible, since Win32 perl implementation simply does not allow that. One is advised to assign to %ENV manually, but only if both NAME and VAL don't have their utf8 bit set, otherwise perl will warn about wide characters.

stat PATH

Same as CORE::stat, except where there is sub-second time resolution provided, returns atime/mtime/ctime entries as floats, same as Time::HiRes::stat.

sv2local TEXT, FAIL_IF_CANNOT = 1

Converts either 8-bit non-utf8-bit or unicode utf8-bit string into a local encoding. May return undef on memory allocation failure, or if TEXT contains unconvertible characters when FAIL_IF_CANNOT = 1

Same as CORE::unlink.

utime ATIME, MTIME, PATH

Same as CORE::utime, except where there is sub-second time resolution provided, accepts atime/mtime/ctime entries as floats, same as Time::HiRes::utime.

AUTHOR

Dmitry Karasik, <dmitry@karasik.eu.org>.

SEE ALSO

Prima, Prima::sys::FS.