Do loop following filevar option in SAS -

data &state.&sheet.;             set di;             retain &header.;             infile in filevar= path end=done missover;               until(done);                  if _n_ =1                     input  &headerlength.;                       input &allvar.;                 output;              end;run; 

variable path in di data set.

i wanna read multiple txt files 1 sas data set. in each txt file first row header , want retain header each observation used if _n_ = 1 input header input second row of other variables analysis.

the output strange. first row contains header , other rows not correct observations.

could me little bit? thank much.

i shenglin chen's answer, here's option: reset row counter 1 each time data step starts importing new file.

data &state.&sheet.;             set di;             retain &header.;             infile in filevar= path end=done missover;               _n_ = 1 1 until(done);                  if _n_ = 1 input &headerlength.;                       input &allvar.;                 output;              end; run; 

this generalises more in case ever want different every nth row within each file.