As suggested here,
$pdflatex = 'pdflatex -interaction=nonstopmode';
$pdf_previewer = "open -a /Applications/Skim.app";
latexmk -pvc -pdf foo.tex
pdflatex has this command-line option:
-interaction=MODE Set the interaction mode; MODE must be one of: batchmode, nonstopmode, scrollmode, errorstopmode.
Edit suggested by @9999years:
Those values are equivalent to a set of LaTeX
\commands that provide the same functionality.
From TeX usage tips:
The modes make TeX behave in the following way:
errorstopmodestops on all errors, whether they are about errors in the source code or non-existent files.
scrollmodedoesn't stop on errors in the source but requests input when a more serious error like like a missing file occurs.
In the somewhat misnamed
nonstopmode, TeX does not request input after serious errors but stops altogether.
batchmodeprevents all output in addition to that (intended for use in automated scripts). In all cases, all errors are written to the log file (yourtexfile.log).