Question: What Is Offset in Linux?

The offset is the current position in the file, as maintained by the kernel for a given file description (see the lseek(2) and open(2) manpages for details).

What is offset of a file?

An offset into a file is simply the character location within that file, usually starting with 0; thus “offset 240” is actually the 241st byte in the file. See relative address. (3) In word processing, the amount of space a document is printed from the left margin.

How do I find the offset of a file?

To get the current offset of an open file, you use lseek() :

1. off_t offset;
2. offset = lseek (fd, 0, SEEK_CUR);
3. if (offset == (offset_t) -1) {
4. perror(“lseek”);
5. return -1;
6. }
7. printf(“fd is currently at offset %jdn”, (intmax_t) offset);