Perl sysseek Function

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Description

This function sets the position within FILEHANDLE according to the values of POSITION and WHENCE.

This is equivalent of the C function lseek( ), so you should avoid using it with buffered forms of FILEHANDLE. This includes the "FILEHANDLE" notation and print, write, seek, and tell. Using it with sysread or syswrite is OK, since they too ignore buffering.

The position within the file is specified by POSITION, using the value of WHENCE as a reference point, as shown below in Table.

EEK_SET -> 0
Sets the new position absolutely to POSITION bytes
within the file

SEEK_CUR -> 1
Sets the new position to the current position plus
POSITION bytes within the file

SEEK_END -> 2
Sets the new position to POSITION bytes, relative to
the end of the file

Syntax

Following is the simple syntax for this function:

sysseek FILEHANDLE,POSITION,WHENCE

Return Value

This function returns undef on failure, a position of 0 is returned as the string 0 but true and Integer, new position (in bytes) on success.

Example

Following is the example code showing its basic usage:


When above code is executed, it produced following result




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