Datasheet

The C and C++ Libraries
ARM DUI 0067D Copyright © 1999-2001 ARM Limited. All rights reserved. 4-83
4.10.9 _sys_seek()
This function puts the file pointer at offset
pos from the beginning of the file.
Syntax
int _sys_seek(FILEHANDLE fh, long pos)
Implementation
This function sets the current read or write position to thenew location
pos relative to
the start of the current file
fh .
Returns
The result is non-negative if no error occurs or is negative if an error occurs.
4.10.10 _sys_istty()
This function determines if a file handle identifies a terminal.
Syntax
int _sys_istty(FILE *f)
Implementation
When a file is connected to a terminal device, this functionis used to provide unbuffered
behavior by default (in the absence of a call to
set(v)buf ) and to disallow seeking.
Returns
The return value is:
0 There is not an interactive device
1 There is an interactive device
other An error occurred.