Re: [CentOS] Re: ls and rm: "argument list too long"

Robert Nichols wrote:

...

These shouldn't make any difference. The limit is on the size of the expanded shell command line.

Really?

$ M=0; N=0; for W in `find /usr -xdev 2>/dev/null`; do M=$(($M+1)); N=$(($N+${#W}+1)); done; echo $M $N 156304 7677373

vs.

$ /bin/echo `find /usr -xdev 2>/dev/null` bash: /bin/echo: Argument list too long

For the first case, the shell never tries to pass the list as command arguments. It builds the list internally, limited only by memory size, and processes the words one by one.

Is that peculiar to bash? I thought the `command` construct was expanded by shells into the command line before being evaluated.