TELL(3C) Standard C Library Functions TELL(3C)
tell - return a file offset for a file descriptor
#include <unistd.h>
off_t tell(int fd);
The tell() function obtains the current value of the file-position
indicator for the file descriptor fd.
Upon successful completion, tell() returns the current value of the
file-position indicator for fd measured in bytes from the beginning
of the file.
Otherwise, it returns -1 and sets errno to indicate the error.
The tell() function will fail if:
EBADF
The file descriptor fd is not an open file descriptor.
EOVERFLOW
The current file offset cannot be represented correctly
in an object of type off_t.
ESPIPE
The file descriptor fd is associated with a pipe or
FIFO.
The tell() function is equivalent to lseek(fd, 0, SEEK_CUR).
See attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT-Level | MT-Safe |
+---------------+-----------------+
lseek(2), attributes(7)
January 28, 1998 TELL(3C)
NAME
tell - return a file offset for a file descriptor
SYNOPSIS
#include <unistd.h>
off_t tell(int fd);
DESCRIPTION
The tell() function obtains the current value of the file-position
indicator for the file descriptor fd.
RETURN VALUES
Upon successful completion, tell() returns the current value of the
file-position indicator for fd measured in bytes from the beginning
of the file.
Otherwise, it returns -1 and sets errno to indicate the error.
ERRORS
The tell() function will fail if:
EBADF
The file descriptor fd is not an open file descriptor.
EOVERFLOW
The current file offset cannot be represented correctly
in an object of type off_t.
ESPIPE
The file descriptor fd is associated with a pipe or
FIFO.
USAGE
The tell() function is equivalent to lseek(fd, 0, SEEK_CUR).
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT-Level | MT-Safe |
+---------------+-----------------+
SEE ALSO
lseek(2), attributes(7)
January 28, 1998 TELL(3C)