22.2.1 Size Limitations

Quite a lot of the Unix vendor implementations of the Bourne shell have a fixed buffer for storing command lines, as small as 512 characters in the worst cases. You may have an error akin to this:

$ ls -d /usr/bin/* | wc -l sh: error: line too long

Notice that the limit applies to the expanded command line, not just the characters typed in for the line. A portable way to write this would be:

$ ( cd /usr/bin && ls | wc -l ) 1556