Function prototype declaration Post: 302866627

Sponsored Content

Top Forums Shell Programming and Scripting Function prototype declaration Post 302866627 by Corona688 on Tuesday 22nd of October 2013 12:40:37 PM

10-22-2013

Registered User

Quote:

Originally Posted by Balasankar

Isn't possibe to decare prototype kind of statement as we do in C++ ?

Nope.

C++ can do that because it's a compiled language. It can assume that "okay, there's a function named xyzzy, I can find its contents later". When the program gets linked together into an exe, it has to actually go find all these libraries to do so.

Shell language runs immediately with no compilation step. If those functions don't already exist, they don't exist. (A few shells might have special features here. These features do not exist in general.)

Even C++ can't manage if you don't tell it what the functions actually are though! At the very least you have to #include <something> before you use them, for it to even assume they exist. You can do something like #include in shell. Put your function, or a bunch of functions, in another file then do this:

Code:

. /path/to/script-name

Note the space between the dot and everything else, that's essential.

script-name will be run in your current shell, effectively loading the functions in it.

Corona688

View Public Profile for Corona688

Visit Corona688's homepage!

Find all posts by Corona688

7 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

Solaris pkgmk -> prototype errors...

I'm attempting to create another package (i.e. for utilizing pkgadd/pkgrm/pkgchk/etc.) But after creating the prototype file, I noticed that some of my files begin with the '=' character. How do I get pkgmk to interpret the "/path/=file" as a single file, rather than interpreting it as...

2. Programming

gcc warnings: implicit declaration of function...

I am having strange warnings from gcc compiler, which I don't think should come while cmpiling. Can anyone help? The warnings are: - warning: implicit declaration of function 'bzero' - warning: implicit declaration of function 'inet_addr' The code is as below: int main(int argc, char...

3. UNIX for Dummies Questions & Answers

Pkgmk....question on prototype file

I've read the man page, but still unclear a bit.... I'm making some packages of files. My pkginfo file has a line BASEDIR=/base/path. I also have several prototype files (depending on the package), that either list the destination path as absolute: f non /abs/path/to/go/here/file1 or are...

4. Programming

implicit declaration of function 'reboot'

Hi, I'm tying to use the following function to reboot the system as part of my code #include <unistd.h> #include <linux/reboot.h> int restart(unsigned int delay) { sleep(delay); return reboot(LINUX_REBOOT_CMD_RESTART); } When I try to compile the code I get the warning in the...

5. UNIX for Dummies Questions & Answers

difficult problem with function declaration

Hello, I have a problem with the declaration of a function. This is how I declare the function : c:63: void foo(threadpool *tp,void (*func)(void*), (void*)arg); Inside main, I call it like this: main(){ .......... threadpool y; c:104: ...

6. What is on Your Mind?

My Charts in the Prototype Vue.js UserCP

Yea.... something I thought would take me an hour ended up taking most of the day. Well, it's not like those YT video tutorials where it take a week or more to make a video and the guys (gals) make it look so easy. But having said that, I'm happy to share with forum members the first "My...

7. What is on Your Mind?

Major Changes in New UserCP (v0.63) Prototype

Regarding the latest version of the UserCP prototype (version 0.63) I have made a lot of major changes, including Added a "Posts Timeline" table for the recent posts, complimenting the non-table version earlier, which has been moved off the main menu (link at the bottom of the table). Added a...

LEARN ABOUT CENTOS

cpanplus::shell

CPANPLUS::Shell(3)					User Contributed Perl Documentation					CPANPLUS::Shell(3)

NAME

       CPANPLUS::Shell - base class for CPANPLUS shells

SYNOPSIS

	   use CPANPLUS::Shell; 	    # load the shell indicated by your
					    # config -- defaults to
					    # CPANPLUS::Shell::Default

	   use CPANPLUS::Shell qw[Classic]  # load CPANPLUS::Shell::Classic;

	   my $ui      = CPANPLUS::Shell->new();
	   my $name    = $ui->which;	    # Find out what shell you loaded

	   $ui->shell;			    # run the ui shell

DESCRIPTION

       This module is the generic loading (and base class) for all "CPANPLUS" shells. Through this module you can load any installed "CPANPLUS"
       shell.

       Just about all the functionality is provided by the shell that you have loaded, and not by this class (which merely functions as a generic
       loading class), so please consult the documentation of your shell of choice.

BUG REPORTS

       Please report bugs or other issues to <bug-cpanplus@rt.cpan.org<gt>.

AUTHOR

       This module by Jos Boumans <kane@cpan.org>.

COPYRIGHT

       The CPAN++ interface (of which this module is a part of) is copyright (c) 2001 - 2007, Jos Boumans <kane@cpan.org>. All rights reserved.

       This library is free software; you may redistribute and/or modify it under the same terms as Perl itself.

SEE ALSO

       CPANPLUS::Shell::Default, CPANPLUS::Shell::Classic, cpanp

perl v5.16.3							    2013-05-20							CPANPLUS::Shell(3)