[augeas-devel] [shellvars] value with spaces

[David Lutterkort]

On Fri, 2008-10-17 at 12:55 +0200, Free Ekanayaka wrote:
> Hi,
> 
> the /etc/default/apmd file contains a variable with a space inside its
> value:
> 
> APMD="--proxy-timeout 30"
> 
> and priting the variable with augtool results in:
> 
> ~$ augtool print /files/etc/default/apmd/APMD
> /files/etc/default/apmd/APMD = "\"--proxy-timeout 30\""

The way this is printed is probably a bad idea, since it's not how you
type it in. Can you file a bug about that inconsistency ?

When augtool splits its command line into tokens, it generally breaks
them at spaces; to have values with spaces you cna enclose them either
in single or douple quotes, but augtool does not understand the escaping
of quote characters (cause I was too lazy to implement it).

In a nutshell, here's various ways to set things interactively with
augtool:
        augtool> set /path " "  # value of path is a single space
        augtool> set /path "'"  # value of path is a single quote
        character
        augtool> set /path '"'  # value of path is a doublequote
        character
        augtool> set /path '" "' # value of path is a dq char, a space, another dq char

> Now, if I try to set a new value, for example "--proxy-timeout 31",
> this won't work, even if I escape the quotes:
> 
> ~$ (echo set /files/etc/default/apmd/APMD "--proxy-timeout 31"; echo save)|augtool
> augtool> Too many arguments for set
> augtool> augtool> 

You need to take into account that the shell has its own ideas about
quoting; the line that augtool gets is the same as typing
        augtool> set /files/etc/default/apmd/APMD --proxy-timeout 31

That's why it's complaining about too many arguments for set.

> ~$ (echo set /files/etc/default/apmd/APMD "\"--proxy-timeout 31\""; echo save)|augtool
> augtool> augtool> Saving failed
> augtool> 

Close, but not quite right: now you're doing the same as
        augtool> set /files/etc/default/apmd/APMD "--proxy-timeout 31"
        augtool> save
that would result in having the line
        APMD=--proxy-timeout 31
in /etc/default and Augeas knows that that is wrong, so it refuses to
save. (The shell would try to run the command '31' with APMD set to
--proxy-timeout when /etc/default is sourced)

What you want (in augtool) is
        augtool> set /files/etc/default/apmd/APMD '"--proxy-timeout 31"'
        augtool> save

>From the shell, that has to be
        ~$ (echo set /files/etc/default/apmd/APMD "'\"--proxy-timeout 31\"'"; echo save)|augtool

Ain't quoting fun ?
David