Danilo at 03:14, 23 January 2022

2022-01-23T03:14:07Z

← Older revision		Revision as of 03:14, 23 January 2022
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			<pageclass class="#3cc882" subcaption="File function"></pageclass>
	__NOTOC__		__NOTOC__
	This function returns whether a stream is readable. If a stream is not readable, then all read operations should result in nil operations (they will return zero bytes read or false if value reading). This state should be immutable across the lifetime of a file/stream class.		This function returns whether a stream is readable. If a stream is not readable, then all read operations should result in nil operations (they will return zero bytes read or false if value reading). This state should be immutable across the lifetime of a file/stream class.

Danilo: Created page with "NOTOC This function returns whether a stream is readable. If a stream is not readable, then all read operations should result in nil operations (they will return zero bytes read or false if value reading). This state should be immutable across the lifetime of a file/stream class. ==Syntax== boolean file:isReadable () ==Returns== Returns '''true''' if the file/stream is readable, '''false''' otherwise. ==Example==
2022-01-19T03:49:51Z

Created page with "NOTOC This function returns whether a stream is readable. If a stream is not readable, then all read operations should result in nil operations (they will return zero bytes read or false if value reading). This state should be immutable across the lifetime of a file/stream class. ==Syntax== <syntaxhighlight lang="lua"> boolean file:isReadable () </syntaxhighlight> ==Returns== Returns '''true''' if the file/stream is readable, '''false''' otherwise. ==Example== <se..."

New page
NOTOC
This function returns whether a stream is readable. If a stream is not readable, then all read operations should result in nil operations (they will return zero bytes read or false if value reading). This state should be immutable across the lifetime of a file/stream class.

==Syntax==
<syntaxhighlight lang="lua">
boolean file:isReadable ()
</syntaxhighlight>

==Returns==
Returns '''true''' if the file/stream is readable, '''false''' otherwise.

==Example==
<section name="Client" class="client" show="true">
This snippet is the counterpart of the [[MTA:Eir/FileSystem/file/isWritable|file.isWritable]] example. It attempts to read the header from the file, but throws an exception if it cannot be read from.
<syntaxhighlight lang="lua">
local function readHeader( theFile )
-- Check whether we can read anything from the file.
if not ( theFile:isReadable() ) then
error( "fatal error: file cannot be read from" );
end

-- Read the generic header back into the engine.
local headerInfo = {
chunkSize = theFile:readUInt(),
version = theFile:readFloat(),
isRaw = theFile:readBoolean()
};

-- Return the header information.
return headerInfo;
end
</syntaxhighlight>
</section>
{{:Modules/FileSystem/file/functions}}