Ok, Denizens. So I have accepted the command line length limits as gospel for quite some time. So, what to do with one's assumptions? Naturally- check them.
I have a Fedora 22 machine at my disposal (meaning: Linux with bash4). I have created a directory with 500,000 inodes (files) in it each of 18 characters long. The command line length is 9,500,000 characters. Created thus:
seq 1 500000 | while read digit; do
touch $(printf "abigfilename%06d\n" $digit);
done
And we note:
$ getconf ARG_MAX
2097152
Note however I can do this:
$ echo * > /dev/null
But this fails:
$ /bin/echo * > /dev/null
bash: /bin/echo: Argument list too long
I can run a for loop:
$ for f in *; do :; done
which is another shell builtin.
Careful reading of the documentation for ARG_MAX states, Maximum length of argument to the exec functions. This means: Without calling exec, there is no ARG_MAX limitation. So it would explain why shell builtins are not restricted by ARG_MAX.
And indeed, I can ls my directory if my argument list is 109948 files long, or about 2,089,000 characters (give or take). Once I add one more 18-character filename file, though, then I get an Argument list too long error. So ARG_MAX is working as advertised: the exec is failing with more than ARG_MAX characters on the argument list- including, it should be noted, the environment data.