Here is the cleaned-up routine I wrote that seems to work under Linux:

#---------------------------------------------------------------------
+----------------------------------------
# Routine:      DoSFTPCommands
# Description:  This routine will take an array of FTP commands and ex
+ecute them using SFTP.
# 
# Input:        
#               aCmdList - Array of FTP commands like: 
#                   "chdir /data/reports"
#                   "rm weekly_rpt_*.csv"
#                   "put /new/reports/weekly_rpt_2004_07_01.csv"
#---------------------------------------------------------------------
+----------------------------------------
sub DoSFTPCommands {
    my (@aCmdList) = @_;

    # Put the FTP commands into a file so we can pass the file name to
+ the SFTP program

    open (CMD_FILE, ">ftp.cmd");
    foreach  (@aCmdList) {
        print CMD_FILE "$_\n";
    }
    close CMD_FILE;

    # Create a Expect script to run SFTP

    my $lCmd = '#!/usr/bin/expect
spawn  sftp  -b ftp.cmd MyAccount@ftp.myCompany.com
expect -exact " password: "
send "myPassword";
interact
';

    open (EXP_FILE, ">auto.exp");
    print EXP_FILE "$lCmd";
    close EXP_FILE;

    # Make the script runable

    system ("chmod +x auto.exp");
    
    # Run the script

    system ("./auto.exp");

    # Clean up by deleting the two files we created

    unlink ("ftp.cmd");
    unlink ("auto.exp");

}   # DoSFTPCommands
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