FSEEK Seek File To A Given Position

Usage

Moves the file pointer associated with the given file handle to the specified offset (in bytes). The usage is

  fseek(handle,offset,style)

The handle argument must be a value and active file handle. The offset parameter indicates the desired seek offset (how much the file pointer is moved in bytes). The style parameter determines how the offset is treated. Three values for the style parameter are understood:

string 'bof' or the value -1, which indicate the seek is relative to the beginning of the file. This is equivalent to SEEK_SET in ANSI C.
string 'cof' or the value 0, which indicates the seek is relative to the current position of the file. This is equivalent to SEEK_CUR in ANSI C.
string 'eof' or the value 1, which indicates the seek is relative to the end of the file. This is equivalent to SEEK_END in ANSI C.

The offset can be positive or negative.

Example

The first example reads a file and then ``rewinds'' the file pointer by seeking to the beginning. The next example seeks forward by 2048 bytes from the files current position, and then reads a line of 512 floats.

--> % First we create the file
--> fp = fopen('test.dat','wb');
--> fwrite(fp,float(rand(4096,1)));
--> fclose(fp);
--> % Now we open it
--> fp = fopen('test.dat','rb');
--> % Read the whole thing
--> x = fread(fp,[1,inf],'float');
--> % Rewind to the beginning
--> fseek(fp,0,'bof');
--> % Read part of the file
--> y = fread(fp,[1,1024],'float');
--> who x y
  Variable Name      Type   Flags             Size
              x     float                    [1 4096]
              y     float                    [1 1024]
--> % Seek 2048 bytes into the file
--> fseek(fp,2048,'cof');
--> % Read 512 floats from the file
--> x = fread(fp,[512,1],'float');
--> % Close the file
--> fclose(fp);