but he went on the give me an example of using execl using a built-in command(date) when I specifically said in the OP that I already have been given an example of using execl with a command ("The only example done in class by the professor was calling the ps command which is a command and not a script.")
It seems to be clearer now where your problem was: between what you called "built-in" programs (I'd call it "system provided executables" and other executable programs there is absolutely no difference. You can (and you found that out yourself already) treat a shell script the same way you treat any other executable, binary or not.
The only difference is that binaries are directly exectuable: they consist of code natively executable on the processor, so once they get loaded they can be executed by it. In contrast scripts are input files for a certain binary - the shells binary, to be precise.
When you execute a shell script the OS will determine its filetype (there is a set of rules laid down in "/etc/magic") and if it comes to the conclusion it is a shell script it will load its default shell and feed it the script as input. If you want to override this and execute it with a different shell (or any other different binary or because your "/etc/magic" lacks the rule to identify what filetype your script is) you can use a "shebang" to specify the commando processor to feed the script to:
Code:
#! /path/to/some/shell/binary
... rest of the script...
will first load this binary and the feed it the scripts text as input. Because for the script language "#!" is still a comment it won't bother the shell at all.
By the way, perderabo has written a whole article about shebangs in the Frequently-Asked-Questions board: The Shebang explained
I hope this helps
bakunin
These 2 Users Gave Thanks to bakunin For This Post:
main()
{
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Hello everyone!
I'm quite new here, but this forum helped me a lot before without registering :-)
I'll go directly to my problem, I have been searching a bit about this issue but I was not successful.
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Muru (2 Replies)
04-22-2014
