You can also use ksh script to feed input files to jmeter. Simple example would be like this

#!/bin/ksh

# Check if folder path is provided
if [ -z "$1" ]; then
    echo "Usage: $0 <folder_path>"
    exit 1
fi

FOLDER_PATH="$1"

# Check if the provided argument is a valid directory
if [ ! -d "$FOLDER_PATH" ]; then
    echo "Error: Directory '$FOLDER_PATH' not found."
    exit 1
fi

# Iterate over .txt files in the folder
for file in "$FOLDER_PATH"/*.txt; do
    # Check if any .txt files exist
    if [ ! -e "$file" ]; then
        echo "No .txt files found in the directory."
        exit 1
    fi
    
    echo "Processing file: $file"
    
    # Run JMeter command with SQL_FILE property
    jmeter -n -t your_test_plan.jmx -JSQL_FILE="$file"

done