Is it accurate to say, the line #!/usr/bin/perl is a command to the Perl program?

Is this considered a perl directive like a shell directive or is it something else in perl?

That line has nothing to do with perl itself..

It is the first line of an executable file (the x-bit), and tells the kernel / shell what interpreter is needed to process the file..

It could be like
'#!/bin/bash' for a bash script,
'#!/bin/sh' for a shell script,
'#!/bin/awk' for an awk script,
'#!/usr/bin/perl' for perl, etc. etc...

You leave out this line and bash (or your shell) won't know how to interpret the file, and will try to do so itself, causing all kinds of errors.

Alternative to using above line would be to call 'perl <filename>' to explicitly tell perl to process the file <filename>.

Hope this helps..

[FYI] That first line is most commonly known as the "shebang line".

i don't think "most commonly" is really right. i reckon it's more common to call it "that thingy at the start" or something. also often called a "hashbang"

Good point. "hashbang", or "shebang" will probably lead you quickest to info on what it is and how to use it.

I knew there was a name for it I couldn't recall.... thanks!

I alays call it "hash ping"

billy

If you don't know the path of perl do,
which perl
/usr/bin/perl
#!<name of interperter program> don't take first # as comment.
so give, #!/usr/bin/perl this in your .pl file