pg_lo_lseek

pg_lo_lseek
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pg_lo_lseek — Seek to a position of a large object

Synopsis

pg_lo_lseek conn descriptor offset whence

Description

pg_lo_lseek moves the current read/write position to offset bytes from the position specified by whence.

Arguments

conn: The handle of the connection.
descriptor: A descriptor for the large object from pg_lo_open.
offset: The new seek position in bytes.
whence: Specified from where to calculate the new seek position: SEEK_CUR (from current position), SEEK_END (from end), or SEEK_SET (from start).

Return Value

The current zero-based byte offset in the large object, after the seek is complete. This is identical to the value which would be returned by pg_lo_tell.

A Tcl error will be thrown if an error occurs.

Notes

All large object manipulation must take place within an SQL transaction block.

This function is limited to using a 32-bit signed offset (about 2GB). See pg_lo_lseek64 for 64-bit offset support.

This command uses or emulates the PostgreSQL libpq function lo_lseek.