Send Linux Tips and Tricks to firstname.lastname@example.org
follow up to issue58/tag/7.html
Mon, 2 Oct 2000 13:38:30 -0400 (EDT)
From: Mathew A Johnston (email@example.com)
I’m not sure that I’m sending this to the right address, but…
I find the most useful tool in the attempt to identify services and their parents to be netstat -ple (process, listening, extended info). This provides a table of listening sockets, the processes that own them, and the uid of the process.
If you’re making an emergency read only anti-hack disk, put this on it – you cant trust your installed version always.
Checking Passwords in Custom Apps
Sun, 08 Oct 2000 14:14:04 -0700
I need to authenticate a user entering a linux os.
I get from the user a username and a password and need to cross it with the /etc/passwd file.
How do I cross the password with the existing one ? (How can I enctypr the password the user entered ?)
I presume what you’re trying to ask is something like: « how can my custom script or application determine if a user has given me the password as would be checked by the system? »
The short answer is that your program should use the getpwent(3) and the crypt(3) library calls.
That is a bit of an oversimplification but here’s a bit more detail:
Technically you don’t « encrypt » the password, you « hash » it and compare your result with the one that’s stored in the /etc/passwd, or the /etc/shadow file, or the one that’s returned by NIS, etc.
Here is a link to a simple example I found using Google:
Glyn Clements is one of the most active and knowlegeable contributors to the linux-admin mailing list.
Printing under Linux
Tue, 10 Oct 2000 09:52:20 -0600
From: Jim (JBRANDV@pnm.com)
In your answer to Gaurav you didn’t mention TurboPrint. I found the current version has full support for my Epson Photo 700 and most other Epson printers as well. I now have full photo quality printing under Linux. Support for other printers is growing daily so keep checking back if you don’t see it the first time. The URL: http://www.turboprint.de
It is beta (0.61) but seems to work great!
Tue, 10 Oct 2000 19:45:00 -0700 (PDT)
From: Buddy Newton (firstname.lastname@example.org)
— « Arne C. Johnson » wrote: what does this subnet does this network give you
192.168.160.1-192.168.175.254 4094 hosts
that’s a 255.255.240.0 mask
The trick is that each « 255 » octet is 8 bits. The number on the end of the slash is a number of bits set on. So, 8 + 8 = 16, still not enough, need 4 bits 4 more! See it’s really just that many 1’s counted from the left… which is to say from the top of the values, so within the third octet, that’s 16 + 32 + 64 + 128 = 240. The netmask 1’s allow bits to « leak through » and establish the network address… the 0’s block or « mask » all the local addresses off. For a lot more detail what this is all about, see Jim Dennis’ fairly verbose « routing and subnetting 101 » in issue 36. — Heather
Sun, 15 Oct 2000 11:46:11 EDT
what are some of the companies that makes « LINUX » operating systems?
There are so many, it is hard to count them… and groups which are not companies also produce their own setups of Linux, so we call them « distributions ».
Linux Weekly News (http://www.lwn.net) has a section dedicated to following this question, and a sidebar that has links to a long list of distro’s – so you should check it out.
Tue, 17 Oct 2000 09:04:19 -0700
anthony buckland wrote:
I live in Japan and would like to replace the Japanese keyboard (buttons) of my NEC laptop with the English keyboard (buttons)–if you know what I mean? Now, do you happen to know of a supplier(s) in the US or elsewhere that I could possibly contact for those English buttons? I thank you, again.
I would contact NEC support via one of the links at http://www.nec.com/support/index.html and see if they can help. Perhaps they can send you the keytops or at least tell you who manufactures them.
How to read Cisco Documentation CDROM on Linux platform
Tue, 17 Oct 2000 08:41:39 -0700
From: Andrea Montefusco
Are you interested to such micro-howto ? Regards
How to read Cisco Documentation CDROM on Linux platform
- mount the cisco cdrom ( mount /dev/cdrom /mnt/cdrom )
- start httpd apache daemon.
- define a virtual server by mean of a listen on a port of your choice id:
You must include a Listen for your virtual servers in your virtual host configuration (specialized file or httpd.conf file); add the following instructions:
Options Indexes FollowSymlinks DocumentRoot /mnt/cdrom AddHandler gunzip .htm Action gunzip /cgi-bin/CiscoDoc
- put in your CGI directory /home/httpd/cgi-bin the following file: (text version)
#!/bin/sh # # echo Content-type:text/html echo FULL_PATH="$DOCUMENT_ROOT""$PATH_INFO" ROOT_FILE="$DOCUMENT_ROOT""/home/home.htm" if [ -f "$ROOT_FILE" ]; then bunzip2 -t "$FULL_PATH" 1> /dev/null 2>&1 rc2=$? if [ "$rc2" = "0" ]; then bunzip2 --stdout "$FULL_PATH" else gunzip -l "$FULL_PATH" 1> /dev/null 2>&1 rc=$? if [ "$rc" = "0" ]; then gunzip --stdout "$FULL_PATH" else cat "$FULL_PATH" fi fi else echo "" echo "
Root file ( » $ROOT_FILE « ) not present
" echo "
Did you forget to insert the CD-ROM ?
" echo "" fi #echo "" echo "" echo "
» echo « Cisco Documentation CDROM Reader ver. 0.3 — A.Montefusco A.Passariello » echo «
" #echo ""
- Make it executable with the command
chmod -c 755 CiscoDoc
- Now you can access Cisco Manuals using URL: « http://localhost:8080/home/home.htm »
A note conserning the article « Making a Simple Linux Network Including
Mon, 11 Sep 2000 12:05:12 +0000
From: Samuli Seppänen (email@example.com)
Instead of doing an « echo 7 > /proc/parport/0/irq » you can put following line to modules.conf:
options parport_pc io=0x378, irq=7
where io / irq should be replaced if necessary. With this you should be able to insmod plip without any problems.
Wanted: articles about non-LILO boot loaders. — Heather
Wed, 27 Sep 2000 22:50:54 -0400
From: « Hoyt » (firstname.lastname@example.org)
Neil Koozer of Roseburg, Oregon has created nuni, a boot loader for a Linux system that uses the ext2 file system and IDE drives.
nuni handles various ext2 block sizes and handles both small and large kernels.
Sat, 30 Sep 2000 17:36:39 +0530
From: Rakesh Tiwari (email@example.com)
From what i understand, u only want to know users begining with « potatoe » in the « Login » coloumn.
$finger | cut -f1 -d » » | grep potatoe
Regards Rakesh Tiwari
If you obey all the rules, you miss all the fun.
2 cent tips – re: Reflections Replacement
Mon, 16 Oct 2000 23:53:00 -0500
From: Rick Cook (firstname.lastname@example.org)
Hi! I would like to access my graphics Linux desktop from my Windows box; I was able to do it using a software called Reflection (I guess you know it), is there any (free) software with the same capabilities of Reflection?
You could also try VNC. If you run a VNC Server on your Linux Machine and a VNC client on your Windows box, you can get a graphical Login (xdm, gdm, kdm) on your Windows Box. See:
The Linux version comes included with several distributions, including Debian.
Tue, 3 Oct 2000 21:12:17 -0400
From: « Barry » (BarryJJ@ATTGlobal.Net)
I bought the ActionTec Internal Call Waiting PCI – not to be confused with the « 56K PCI Pro » which is labelled as a WinModem – ‘coz it was the only one that mentioned Linux support on the box and was PCI. From this I assumed it to be a « real » modem.
I haven’t actually tried it under Linux yet, but I was impressed to find the instruction book had more pages (10) devoted to getting it to work under Linux than for the Windows variants. And there is no mention of having to install special software … at least none that I can find.
There are separate headings for PPP, GNOME Dialer Applet, KPPP, linuxconf Dialer, and even a paragraph on minicom. It cites the instructions as having been verified under Red Hat 5.2 and 6.0, although I found references to my current distribution of choice – SuSE – on their web pages.
I was impressed! Their web site is www.actiontec.com
HTH … BJ
authentication pam and kde
Mon, 23 Oct 2000 08:25:49 -0700
From: Breen Mullins
At 11:42 AM +0200 10/23/00, Dean Buhrmann wrote:
Kapil Sharma gave in the Oktober issue a few security tips. One is blocking users from doing su and only allowing the users from group wheel to do so. [snip]
It works well in virtual terminals. In KDE however it is now impossible to su. Authentication rejects now always the root password.
Hi Dean –
This also fails in Gnome if I use the default terminal. Try opening a vanilla xterm – I can su if I do it there.
Printing in Netscape
Wed, 25 Oct 2000 12:15:56 -0700
In issue 57 (http://www.linuxgazette.com/issue57/lg_tips57.html), Matthew Willis suggested using psnup to print two pages per sheet in Netscape.
psnup -c -n 2 | lpr -pprinter
I had to change this slightly to get it to work for me. I use:
psnup -c -n 2 -pletter | lpr
The « -pletter » option says you’re using letter-sized paper (the normal page size in the US). Otherwise it will default to the European A4 size. If you print A4-formatted pages on letter paper, the rightmost part of the content runs off the edge of the page.
The « -pprinter » option didn’t work for me. I assume Matthew was trying to select the printer device. According to my lpr manpage, the option would be « -P printer ». « -p » filters the input through pr, which isn’t what we want. (The pr command formats text files.)
— Mike Orr