passing arguments to alias in .bash_profile

Question

Level 1

25 points

passing arguments to alias in .bash_profile

Hello

I have defined this alias in my .bash_profile :


alias duk='du -k | sort -rn | grep -v "/.*/"'

This works fine if for the current working dir by just typing "duk" but when i pass any argument e.g. "duk abc/def " it doesn't print anything. How do i pass an argument in this alias ?

Thanks

PowerBook G4 15", Mac OS X (10.5.5), 1.5GHz/512MB/80GB

Posted on Nov 21, 2008 4:10 AM

Reply

Answer 1

kanny Author

Level 1

25 points

Nov 21, 2008 4:47 AM in response to kanny

I changed from alias to function :


duk1 () {
 du -k $* | sort -rn | sed -e 's/$*//' | grep -v "/.*/"
}

Though this solves the issue of passing the argument, but the sed as always creates problem. Now how to get that argument inside the sed ?

Reply

Answer 2

kanny Author

Level 1

25 points

Nov 21, 2008 5:31 AM in response to kanny

Ok, finally i have things working :


duk() {
 du -k $* | sort -rn | grep -v "$/./" | sed -e 's/[a-zA-Z0-9>*///'
}

Still sed is not very friendly otherwise i would have liked perl-like syntax "s/[w>*///" .

Reply

Answer 3

kanny Author

Level 1

25 points

Nov 21, 2008 5:43 AM in response to kanny

This breaks though when the argument has space in it e.g. "This Folder" .

Reply

Answer 4

etresoft

Level 9

56,596 points

Nov 21, 2008 5:43 AM in response to kanny

When using an alias you don't have much control over how to re-order the arguments. Your typed-in arguments just get tacked on the end.

You have much more flexibility if you just create a new shell script and put it into a handy "bin" directory somewhere in your path. I have 36 such scripts.

Your new duk script would look something like this:


#!/bin/sh
du -k ${*} | sort -rn | grep -v "/.*/"

Reply

Answer 5

BobHarris

Level 9

56,921 points

Nov 21, 2008 6:53 AM in response to kanny

This breaks though when the argument has space in it e.g. "This Folder" .

Change your $* to "$@" (see below):


duk() {
 du -k "$@" | sort -rn | grep -v "$/./" | sed -e 's/[a-zA-Z0-9>*///'
}

The 4 character sequence "$@" has special shell magic. From the bash man page:

When the expansion occurs within double quotes,
each parameter expands to a separate word.
That is, "$@" is equivalent to "$1" "$2" "$3" ...

Reply

Answer 6

kanny Author

Level 1

25 points

Nov 21, 2008 8:15 AM in response to kanny

I tried both $@ and ${*} and they don't address the problem of preserving the spaces in Folder names


[21:38 ~]$ duk Documents/Ulead Slide Show/
du: Documents/Ulead: No such file or directory
du: Slide: No such file or directory
du: Show/: No such file or directory

I think there was slight misunderstanding. I need to preserve the spaces in arguments while the suggestions seem to be for treating multiple arguments passed to the function. I read through the length of the bash man page, but still no avail. Any hints ?

Reply

Answer 7

kanny Author

Level 1

25 points

Nov 21, 2008 8:32 AM in response to kanny

Oh my bad.

Thanks Bob. I missed on 4-character magic. Using *"$@"* does solve the problem. Even "$*" also works.

Thanks

Reply