topic Re: perl split function question in Operating System - HP-UX

perl split function question

Jeff Picton — Thu, 16 Oct 2003 10:16:26 GMT

Hi

I have a mixed delimiter password file with both : and ,,,.

How can I use the perl split function to load the password file into an array without the delimeters ?

I know this is easy with awk but what about split ?

Jeff

Re: perl split function question

Brian Bergstrand — Thu, 16 Oct 2003 11:04:48 GMT

@pwent = split(/:/, $_);
@gecos = split(/,/, $pwent[4]);

HTH.

Re: perl split function question

Paddy_1 — Thu, 16 Oct 2003 11:08:00 GMT

Here is a example that can serve to help :
word can be split into characters, a sentence split into words and a paragraph split into sentences:

@chars = split(//, $word);
@words = split(/ /, $sentence);
@sentences = split(/\./, $paragraph);

Re: perl split function question

Jeff Picton — Thu, 16 Oct 2003 11:14:12 GMT

Hi

Thats fine but I need to print the WHOLE file (as an array) without delimeters. Brians suggestion only enables one to print a single field of the array.

Re: perl split function question

Brian Bergstrand — Thu, 16 Oct 2003 11:25:05 GMT

I'm not sure what you mean. You want each line of the file as a separate entry in an array? And each entry should be void of the : and , delimeters?

Could you better describe your requirements?

Thanks.

Re: perl split function question

Jordan Bean — Fri, 17 Oct 2003 02:00:06 GMT

You actually have two distinct options: split and getpwent. The latter works on the system passwd file only.

If you want to sort, then I'd use a hash. Otherwise, I'd print each line as its read and munged. A simple array isn't necessary.

I'm pulling the following snippets from memory, so please excuse any errors.

1. No sorting:

perl -pe 'tr/:,/ /;' < passwd > passwd.out

2. Sorting:

$h={};
while(<>){ chomp; ($u,@u)=split /[:,]/; $h->{$u}=[@u]; }
foreach ( sort keys %$h ) { printf '%s 'x9."\n", $_, @{$h->{$_}}; }

3. System routine. No sorting:

setpwent;
while(@_=getpwent){printf '%s 'x9."\n",@_;}
endpwent;

4. System routine. Sorted:

$h={};
setpwent;
while(($u,@u)=getpwent){ $h->{$u}=[@u]; }
endpwent;
foreach ( sort keys %$h ) { printf '%s 'x9."\n", $_, @{$h->{$_}}; }

It's late. Let me know if I goofed.

Re: perl split function question

Mark Grant — Fri, 17 Oct 2003 02:41:15 GMT

If I understand the question correctly you want to finish up with one array that contains every line of the password file but without delimiters. Simplest thing here is to just translate all the delimiters to spaces as in "tr /:/ /;" and "tr /,/ /;" and "push" the result onto an array.

If you want to access each individual field of each individual line of the file you will need a multi-dimentional array. Multi-dimentional arrays are a pain in perl, in my view so I would go with the previous suggest and make a hash of arrays. First translate the ","'s to spaces (or to ":" if you want them as seperate fields) then split on the ":" into an array which you then put into a hash as in "$myhash{$array[0]}=[ @array ].

You would access an user fred'd uid for example with $myhash{fred}[2].

Re: perl split function question

H.Merijn Brand (procura — Fri, 17 Oct 2003 03:33:36 GMT

Why not use perl's buildin functions to access the password file info?

perldoc -f endpwent
perldoc -f getpwent
perldoc -f getpwnam
perldoc -f getpwuid
perldoc -f setpwent

Enjoy, have FUN! H.Merijn

Re: perl split function question

Jeff Picton — Fri, 17 Oct 2003 03:41:47 GMT

Hi

Thanks for all the replies.

I tried the sort method but there is a syntax error on the printf statement which I cannot find

Jeff

Re: perl split function question

Jordan Bean — Sat, 18 Oct 2003 06:41:01 GMT

Hmm. Interesting. Put a space between '%s 'x9 and ."\n".