Create an alias for IRSFRINGE. For example, if you untarred the package in the directory /home/joe/irsfringe_v1.1:
alias irsfringe '/home/joe/irsfringe_v1.1/IRSFRINGE'
Start the IRSFRINGE IDL tool by typing the following alias command in the running directory:
Read in the IRS product, for example, "SPITZER_S3_5638912_17_1_E173247_tune.tbl", stored in the "data/" sub-directory. Note that IRSFRINGE can only be used on the IRS products that come out of the extraction (post-BCD) pipeline, namely those with the filename suffix spect.tbl, spect2.tbl, or tune.tbl (see Archive Pipeline Products for IRS).