filemod – Provide file modification times, and compare them

The pack­age pro­vides macros to read and com­pare the mod­i­fi­ca­tion dates of files. The files may be .tex files, im­ages or other files (as long as they can be found by LaTeX). It uses the \pdf­file­mod­date prim­i­tive of pdfLaTeX to find the file mod­i­fi­ca­tion date as PDF date string, parses the string and re­turns the value to the user. The pack­age will also work for DVI out­put with re­cent ver­sions of the LaTeX com­piler which uses pdfLaTeX in DVI mode. The func­tion­al­ity is pro­vided by purely ex­pand­able macros or by faster but non-ex­pand­able ones.