pSOSystem System Calls - Read

lseek_f pHILE+ System Calls
lseek_f Repositions for read or write within an open file.
#include
unsigned long lseek_f(
unsigned long fid, /* file identifier */
unsigned long position, /* relative seek vector */
long offset, /* offset */
unsigned long *old_lptr /* previous L_ptr */
)
Volume Types
Description
Arguments
All volume types.
lseek_f() repositions the L_ptr associated with an open file connection. Each file
connection has its own L_ptr, and it points to the next byte to be read or written in
the file. Repositioning can be specified relative to the beginning of the file, the
current L_ptr, or the end of the file.
fid Specifies the file identifier associated with the file.
position Defines how to reposition L_ptr and must have one of the
following values:
Value Meaning
0 Offset from beginning of file
1 Offset from current L_ptr
2 Offset from end of file
offset Specifies the number of bytes to move L_ptr. A negative
offset moves L_ptr backwards.
old_lptr Points to the variable where lseek_f() stores the previous
value of the L_ptr.
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