FileSetPos: Difference between revisions
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__NOTOC__ | __NOTOC__ | ||
{{Server function}} | {{Server client function}} | ||
Sets the current read/write position in the file. | Sets the current read/write position in the file. | ||
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int fileSetPos ( file theFile, int offset ) | int fileSetPos ( file theFile, int offset ) | ||
</syntaxhighlight> | </syntaxhighlight> | ||
{{OOP||[[file]]:setPos|pos|fileGetPos}} | |||
===Required Arguments=== | ===Required Arguments=== | ||
*'''theFile:''' The file handle of which you want to change the read/write position. | *'''theFile:''' The file handle of which you want to change the read/write position. | ||
*'''offset:''' The new position. This is the number of bytes from the beginning of the file. | *'''offset:''' The new position. This is the number of bytes from the beginning of the file. If this value is larger than the file size, it is limited to 52,428,800 bytes (50 MB). | ||
===Returns=== | ===Returns=== | ||
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fileClose(hFile) -- close the file | fileClose(hFile) -- close the file | ||
else | else | ||
outputConsole("Unable to open | outputConsole("Unable to open test.dat") | ||
end | end | ||
</syntaxhighlight> | </syntaxhighlight> | ||
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==See Also== | ==See Also== | ||
{{File functions}} | {{File functions}} | ||
[[pt-br:fileSetPos]] | |||
Latest revision as of 20:03, 20 December 2023
Sets the current read/write position in the file.
Syntax
int fileSetPos ( file theFile, int offset )
OOP Syntax Help! I don't understand this!
- Method: file:setPos(...)
- Variable: .pos
- Counterpart: fileGetPos
Required Arguments
- theFile: The file handle of which you want to change the read/write position.
- offset: The new position. This is the number of bytes from the beginning of the file. If this value is larger than the file size, it is limited to 52,428,800 bytes (50 MB).
Returns
Returns where the offset was actually set at. I.e. if offset was past the end of the file, it will be set at the end of the file, and this position will be returned. Returns false in case of failure (e.g. the specified file handle is invalid).
Example
This example opens a binary file and prints the value of the byte at position 8 to the console.
local hFile = fileOpen("test.dat") -- attempt to open the file
if hFile then -- check if it succeeded
fileSetPos(hFile, 8) -- set the read/write position
local readByte = fileRead(hFile, 1) -- read one byte from this position
outputConsole("Byte at position 8 = " .. string.byte(readByte)) -- output it
fileClose(hFile) -- close the file
else
outputConsole("Unable to open test.dat")
end