Problem with (Understanding) function Post: 302993154

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Top Forums Shell Programming and Scripting Problem with (Understanding) function Post 302993154 by drysdalk on Tuesday 7th of March 2017 10:05:57 AM

03-07-2017

Registered User

Hi,

The problem is that (unless I'm missing something here) your syntax, as it stands, isn't valid and so won't work at all.

For example, you have a line like this in your function:

return RETVAL

In Bash, the 'return' function can only return a single numeric value. It should be thought of as the exit value of the function, more or less. You can't return a full alphanumeric string, and so this approach isn't valid. No function in Bash can ever pass back a string by using 'return'.

Secondly, you are using syntax like this in your output:

echo -e $LZ"Test"

Here you're mixing up variables with functions. If you want to call the function 'LZ', you have to do it by essentially treating it as a command name (like 'Log' in my earlier example). Bash will always treat $LZ as the contents of a variable called 'LZ', and not as a function. So the value of it will never change and will always be the same, unless you subsequently change it yourself.

So again unless I'm missing something in your explanation (which I certainly grant I may very well be), then you are going to have to re-write this so that the function is defined correctly, and that your output is generated by calling it correctly.

If you feel there's something I've not grasped here or if you have any other info that might clear things up, then please let me know and I'll be happy to assist further.

drysdalk

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LEARN ABOUT SUNOS

endusershell

getusershell(3C)					   Standard C Library Functions 					  getusershell(3C)

NAME

       getusershell, setusershell, endusershell - get legal user shells

SYNOPSIS

       #include <unistd.h>

       char *getusershell(void);

       void setusershell(void);

       void endusershell(void);

DESCRIPTION

       The  getusershell()  function  returns  a  pointer  to  a  legal  user  shell  as defined by the system manager in the file /etc/shells. If
       /etc/shells does not exist, the following locations of the standard system shells are used in its place:

       /bin/bash		  /bin/csh
       /bin/jsh 		  /bin/ksh
       /bin/pfcsh		  /bin/pfksh
       /bin/pfsh		  /bin/sh
       /bin/tcsh		  /bin/zsh
       /sbin/jsh		  /sbin/pfsh
       /sbin/sh 		  /usr/bin/bash
       /usr/bin/csh		  /usr/bin/jsh
       /usr/bin/ksh		  /usr/bin/pfcsh
       /usr/bin/pfksh		  /usr/bin/pfsh
       /usr/bin/sh		  /usr/bin/tcsh
       /usr/bin/zsh		  /usr/xpg4/bin/sh

       The getusershell() function opens the file /etc/shells, if it exists, and returns the next entry in the list of shells.

       The setusershell() function rewinds the file or the list.

       The endusershell() function closes the file, frees any memory used by getusershell() and setusershell(), and rewinds the file /etc/shells.

RETURN VALUES

       The getusershell() function returns a null pointer on EOF.

BUGS

       All information is contained in memory that may be freed with a call to endusershell(), so it must be copied if it is to be saved.

SunOS 5.10							    30 Aug 2004 						  getusershell(3C)