[SOLVED] I get pattern error when running cov-analysis --tu-patern

I am trying to run the following in a makefile

 /home/pagl_home/bin/SI.docker_17cy/bin/pagl-build-env run -b '/home/SI/YYYY' -w '../XXX' \
--objdir '' -c '/home/coverity/cov-analysis-linux64-2018.06/bin/cov-analyze --dir XXX ... \
--coding-standard-config /home/coverity/cov-analysis-linux64-2018.06/config/coding-standards/misrac2012/misrac2012-all.config /
--paths 100000  --tu-pattern "file('.*\.c$')";'

I get the following error because of -c ' --tu-pattern "file('.*\.c$')";'

Illegal character in pattern: .

How can i write the pattern so it will consider only c file?

Thanks

but i get the error