[gentoo-user] Re: [SOLVED]Re: [A bit off-topic] Bash alias and &

[Jonathan Callen]

On 06/12/2016 11:54 AM, Andrew Lowe wrote:
> On 06/12/16 23:07, Andrew Lowe wrote:
>> On 06/12/16 22:43, Alan McKinnon wrote:
>>> On 12/06/2016 16:33, Nico Verrijdt wrote:
>>>> Hi Andrew,
>>>>
>>>> 2016-06-12 16:26 GMT+02:00 Andrew Lowe <agl@×××××××.au
>>>> <mailto:agl@×××××××.au>>:
>>>>
>>>>     Hi all,
>>>>              A bit off topic here, but there are plenty of people who
>>>>     seem to know their shells back to front so here goes.
>>>>
>>>>              I have set up a Win32 based development environment,
>>>>     bash/cc/ls/etc/etc, for 1st year Engineering students who have to
>>>>     learn C on a command line. It's fine for me to remember to put
>>>> the &
>>>>     at the end of the command when I fire up the editor but for them,
>>>>     it's major angst.
>>>>
>>>>              The first thing that comes to mind is an alias. Just off
>>>>     the top of my head I tried:
>>>>
>>>>              alias "npp=npp %1 &"
>>>>
>>>> Shouldn't this be: alias npp="npp %1 &"  ?
>>>>
>>>>
>>>>     npp being the editor, but that didn't work. Is an alias the
>>>>     best/easiest way to do this and if so, what would the syntax be, or
>>>>     is there a better way?
>>>>
>>>>              Any thoughts, greatly appreciated,
>>>>
>>>>                      Andrew
>>>>
>>>>
>>>> Hope this helps,
>>>> Nico
>>>
>>>
>>> Or just tell them to remember to add the & at the end.
>>> With an alias what will they do when they don't want it?
>>>
>>> Or look at it this way:
>>>
>>> It's syntax, it's important. C is probably more syntax-critical than any
>>> other language around (binds to the right, anyone?) so what's the
>>> problem with requiring correct syntax on the command line as well?
>>>
>>> Obligatory disclaimer: I've recently had a bellyache full of dumb people
>>> who insist I put code when a human (themselves) belongs...
>>>
>>     Yes, I agree BUT, this is a "half subject" in a common first year of
>> an Engineering degree. These are people who will become
>> Civil/Mechanical/Electrical/Chemical Engineers and they have no desire
>> to learn programming. To put it bluntly, all they are interested in is
>> their car, getting drunk and trying to get a root - the order may vary,
>> but that is the top three priorities. Anything else is just too much to
>> think about.
>>
>>     In reality, I'm doing this to make my life easier. As much as I tell
>> them to do something, write up documents that tell them what to do and
>> reiterate what they have to do, I still get the question "It's broken,
>> it won't do as I want...."
>>
>>     Andrew
>>
>> p.s. Nico's point was a typo on my part in the email.
>>
>
>     Simple answer to this which a single google search found. You CAN'T
> pass parameters to an alias under Bash. You need to do a function. A
> simple function of:
>
> npp()
> {
>     npp $1 &
> }
>
> was all I needed.
>
>     Andrew
>
>

A better function for the same (that also doesn't loop forever because
the function might be calling itself):

npp() {
    command npp "$@" &
}

This allows any number of arguments to be passed, instead of "exactly
one" and allows filenames containing spaces, etc. to be passed correctly.

-- 
Jonathan Callen