I can see only two reasons for manually parsing /etc/passwd:

To learn handling CSV files, there are much better ways. And even then, Text::CSV and Text::CSV_XS are the better way to handle CSV files, simply because those modules are prepared to handle all the nasty edge cases you didn't think about.

Verifying a username and/or home directory does not seem like "very special needs".

You probably just want to use getpwnam in list context, i.e.:

my ($name, $passwd, $uid, $gid, $quota, $comment, $gcos, $dir, $shell,
+ $expire) = getpwnam($login);

[download]

User::pwent wraps that into a nice object:

use User::pwent; # <-- replace getpwnam() and friends with functions r
+eturning objects
my $rec = getpwnam($login);
say $rec->name,' has UID ',$rec->uid,', home ',$rec->dir,', shell ',$r
+ec->shell;

[download]

What's the difference to reading /etc/passwd?

The second point is important: /etc/passwd is no longer the only source of user information, since at least three decades. NSS allows to add more records from other sources (NIS, NIS+, LDAP, AD, ...), and it should also allow to ignore /etc/passwd completely. PAM allows to do even more crazy stuff.

The same applies to /etc/group and the getgr... functions, and also to /etc/services (getserv...), /etc/hosts (gethost...), /etc/protocols (getproto...).

At work, all user and group information resides in a Samba 4 Active Directroy database (essentialy LDAP plus some extras), and the /etc/passwd on all Linux systems is at the bare minimum, just root and some system/daemon accounts. If you had an AD account, you could login into any Linux box, but you would not find your login in /etc/passwd. getpwnam works fine, and would return your user record, because at the C library level, LDAP would be queried and return your user record. Plus, it would continue to do so if we switched from AD to NIS+ or some fancy SQL database holding user records.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re: Trying to take user input as username, read etc/passwd and output user ID by afoken
in thread Trying to take user input as username, read etc/passwd and output user ID by charlesx1552

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