How to iterate over positional parameters in a Bash script?

Question

Where am I going wrong?

I have some files as follows:

filename_tau.txt
filename_xhpl.txt
filename_fft.txt
filename_PMB_MPI.txt
filename_mpi_tile_io.txt

I pass tau, xhpl, fft, mpi_tile_io and PMB_MPI as positional parameters to script as follows:

./script.sh tau xhpl mpi_tile_io fft PMB_MPI

I want grep to search inside a loop, first searching tau, xhpl and so on..

point=$1     #initially points to first parameter
i="0"
while [$i -le 4]
do
  grep "$str" ${filename}${point}.txt
  i=$[$i+1]
  point=$i     #increment count to point to next positional parameter
done

Answer 1

Set up your for loop like this. With this syntax, the loop iterates over the positional parameters, assigning each one to 'point' in turn.

for point; do
  grep "$str" ${filename}${point}.txt 
done