MQL4参考标准常量，列举和架构输入/输出常量 内部文件位置

Positioning Inside a File

Most of file functions are associated with data read/write operations. At the same time, using the FileSeek() you can specify the position of a file pointer to a position inside the file, from which the next read or write operation will be performed. The ENUM_FILE_POSITION enumeration contains valid pointer positions, relative to which you can specify the shift in bytes for the next operation.

ENUM_FILE_POSITION

Identifier	Description
SEEK_SET	File beginning
SEEK_CUR	Current position of a file pointer
SEEK_END	File end