Ttyjfyk

What would be the most expensive material to an intergalactic society?

Making a kiddush for a girl that has hard time finding shidduch

Professor forcing me to attend a conference, I can't afford even with 50% funding

Called into a meeting and told we are being made redundant (laid off) and "not to share outside". Can I tell my partner?

In the late 1940’s to early 1950’s what technology was available that could melt a LOT of ice?

How many characters using PHB rules does it take to be able to have access to any PHB spell at the start of an adventuring day?

Confusion about Complex Continued Fraction

Does Christianity allow for believing on someone else's behalf?

Are all players supposed to be able to see each others' character sheets?

What do *foreign films* mean for an American?

Was it really inappropriate to write a pull request for the company I interviewed with?

Has a sovereign Communist government ever run, and conceded loss, on a fair election?

Is it possible to avoid unpacking when merging Association?

Doesn't allowing a user mode program to access kernel space memory and execute the IN and OUT instructions defeat the purpose of having CPU modes?

Is it a Cyclops number? "Nobody" knows!

Trig Subsitution When There's No Square Root

Getting the || sign while using Kurier

Can the alpha, lambda values of a glmnet object output determine whether ridge or Lasso?

Can one live in the U.S. and not use a credit card?

What materials can be used to make a humanoid skin warm?

I reported the illegal activity of my boss to his boss. My boss found out. Now I am being punished. What should I do?

Can I negotiate a patent idea for a raise, under French law?

Why aren't there more Gauls like Obelix?

Why couldn't the separatists legally leave the Republic?

Linux shell script to check if another user has unread mail

What is/are the standard CLI program(s) to manage users and groups?Why does the 'bin' user need a login shell?Automate checking user submitted filesMultiple Lan interfaces on one VM rather than multiple VMGmail instant new mail notifier for Debian 7 systems?Setting up receive-only mail server and handling incoming mail and attachmentsMail one liner to check if null before sendingHow do I create a local mail account?Running script through ssh and evaluate some var/comand inside the host machineScript or makefile to automate new user creation?

2

I'm looking to create a shell script that will accept userids as an argument to check if that user has unread mail in /var/spool/mail.

How would I even go about checking a user's mail status? Is /var/spool/mail only unread mail? If so, then I'm assuming I would just check for users with files of size greater than 0.

linux email

share|improve this question

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

bumped to the homepage by Community♦ 34 mins ago

This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  will this script be running as root, and does it need to be portable?
  
  – thrig
  Dec 11 '17 at 23:53
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  No it will not, and no it doesn't need to be portable.
  
  – linuxnewbie
  Dec 12 '17 at 0:11
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  you can get only the file size (unless something set a looser umask than my MTA does) but that will not tell you whether the mail has been read or not
  
  – thrig
  Dec 12 '17 at 0:58
  

  
  
  
  

add a comment | 

2

I'm looking to create a shell script that will accept userids as an argument to check if that user has unread mail in /var/spool/mail.

How would I even go about checking a user's mail status? Is /var/spool/mail only unread mail? If so, then I'm assuming I would just check for users with files of size greater than 0.

linux email

share|improve this question

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

bumped to the homepage by Community♦ 34 mins ago

This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  will this script be running as root, and does it need to be portable?
  
  – thrig
  Dec 11 '17 at 23:53
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  No it will not, and no it doesn't need to be portable.
  
  – linuxnewbie
  Dec 12 '17 at 0:11
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  you can get only the file size (unless something set a looser umask than my MTA does) but that will not tell you whether the mail has been read or not
  
  – thrig
  Dec 12 '17 at 0:58
  

  
  
  
  

add a comment | 

I'm looking to create a shell script that will accept userids as an argument to check if that user has unread mail in /var/spool/mail.

How would I even go about checking a user's mail status? Is /var/spool/mail only unread mail? If so, then I'm assuming I would just check for users with files of size greater than 0.

linux email

share|improve this question

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

share|improve this question

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

share|improve this question

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

edited Dec 19 '17 at 1:53

Jeff Schaller

43.2k1159138

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

asked Dec 11 '17 at 23:26

linuxnewbielinuxnewbie

111

2 Answers
2

active

oldest

votes

0

You could use mailx (formerly mail) command with options -e and u:

-e Just check if mail is present in the system mailbox. If yes, return an exit status of zero, else, a non-zero value.

-u user
Reads the mailbox of the given user name.

To allow non-root user to check the other user's email you have to create a sudo rule in the /etc/sudoers file that will allow that user to run mailx as root, e.g.:

fred localhost=/bin/mailx -e -u *

check man sudoers for the complete format.

Then you just test the exit status of

sudo mailx -e -u tom

executed by fred

share|improve this answer

edited Dec 12 '17 at 1:49

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This looks like a great method, but I forgot to mention that I don't have root access.
  
  – linuxnewbie
  Dec 12 '17 at 1:54
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie what keeps you from asking administrator to set the things for you if your intents are legitimate?
  
  – Serge
  Dec 12 '17 at 2:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  because this is a script/awk assignment and i'm only allowed to work with the permissions I currently have.
  
  – linuxnewbie
  Dec 12 '17 at 2:59
  

  
  
  
  

add a comment | 

0

One method that is used to find unread mail is to check the timestamps on the mail spool file. If the file was written to after it was accessed (read), i.e. its mtime is greater than atime, then there is unread mail:

for f in /var/spool/mail/* ; do 
 [ $(stat -c '%Y -gt %X' "$f") ] && echo "$f has unread mail"
done

That of course considers everything in the mailbox as "read" after it's opened, regardless of if anyone looked at the individual messages.

In many cases, read messages are also moved away from the spool directory (to ~/mbox), so you could do with just checking the file size.

share|improve this answer

edited Dec 12 '17 at 7:37

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I forgot to mention I don't have root access, will this still work? Also how does this script take in the userid as an argument? I need to check specific users.
  
  – linuxnewbie
  Dec 12 '17 at 1:56
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  To my understand the /var/spool/mail/ directory is a temporary directory that only holds unread mail. Once it is opened it is either deleted or moved to a different directory thats dedicated to the user. So I should be able to see if the user has unread mail in there just based off of the directory size. I'm just not sure if all of this adds up lol
  
  – linuxnewbie
  Dec 12 '17 at 1:59
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie, you only need x access to the directory to stat a file, and you have that anyway, since otherwise you couldn't reach your own mail spool file. Of course, as written, it doesn't take an argument, but that's not a very hard exercise (start here: [Tests and Conditionals])mywiki.wooledge.org/BashGuide/TestsAndConditionals) and the stat(1) man page). And sure, checking the size might be enough too. Depends on how the user works with their mailbox.
  
  – ilkkachu
  Dec 12 '17 at 7:42
  

  
  
  
  

add a comment | 

Your Answer

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "106"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2funix.stackexchange.com%2fquestions%2f410305%2flinux-shell-script-to-check-if-another-user-has-unread-mail%23new-answer', 'question_page');

);

Post as a guest

Name

Email

Required, but never shown

0

You could use mailx (formerly mail) command with options -e and u:

-e Just check if mail is present in the system mailbox. If yes, return an exit status of zero, else, a non-zero value.

-u user
Reads the mailbox of the given user name.

To allow non-root user to check the other user's email you have to create a sudo rule in the /etc/sudoers file that will allow that user to run mailx as root, e.g.:

fred localhost=/bin/mailx -e -u *

check man sudoers for the complete format.

Then you just test the exit status of

sudo mailx -e -u tom

executed by fred

share|improve this answer

edited Dec 12 '17 at 1:49

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This looks like a great method, but I forgot to mention that I don't have root access.
  
  – linuxnewbie
  Dec 12 '17 at 1:54
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie what keeps you from asking administrator to set the things for you if your intents are legitimate?
  
  – Serge
  Dec 12 '17 at 2:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  because this is a script/awk assignment and i'm only allowed to work with the permissions I currently have.
  
  – linuxnewbie
  Dec 12 '17 at 2:59
  

  
  
  
  

add a comment | 

0

You could use mailx (formerly mail) command with options -e and u:

-e Just check if mail is present in the system mailbox. If yes, return an exit status of zero, else, a non-zero value.

-u user
Reads the mailbox of the given user name.

To allow non-root user to check the other user's email you have to create a sudo rule in the /etc/sudoers file that will allow that user to run mailx as root, e.g.:

fred localhost=/bin/mailx -e -u *

check man sudoers for the complete format.

Then you just test the exit status of

sudo mailx -e -u tom

executed by fred

share|improve this answer

edited Dec 12 '17 at 1:49

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This looks like a great method, but I forgot to mention that I don't have root access.
  
  – linuxnewbie
  Dec 12 '17 at 1:54
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie what keeps you from asking administrator to set the things for you if your intents are legitimate?
  
  – Serge
  Dec 12 '17 at 2:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  because this is a script/awk assignment and i'm only allowed to work with the permissions I currently have.
  
  – linuxnewbie
  Dec 12 '17 at 2:59
  

  
  
  
  

add a comment | 

You could use mailx (formerly mail) command with options -e and u:

-e Just check if mail is present in the system mailbox. If yes, return an exit status of zero, else, a non-zero value.

-u user
Reads the mailbox of the given user name.

To allow non-root user to check the other user's email you have to create a sudo rule in the /etc/sudoers file that will allow that user to run mailx as root, e.g.:

fred localhost=/bin/mailx -e -u *

check man sudoers for the complete format.

Then you just test the exit status of

sudo mailx -e -u tom

executed by fred

share|improve this answer

edited Dec 12 '17 at 1:49

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

fred localhost=/bin/mailx -e -u *

sudo mailx -e -u tom

share|improve this answer

edited Dec 12 '17 at 1:49

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

answered Dec 12 '17 at 1:15

SergeSerge

5,70521325

0

One method that is used to find unread mail is to check the timestamps on the mail spool file. If the file was written to after it was accessed (read), i.e. its mtime is greater than atime, then there is unread mail:

for f in /var/spool/mail/* ; do 
 [ $(stat -c '%Y -gt %X' "$f") ] && echo "$f has unread mail"
done

That of course considers everything in the mailbox as "read" after it's opened, regardless of if anyone looked at the individual messages.

In many cases, read messages are also moved away from the spool directory (to ~/mbox), so you could do with just checking the file size.

share|improve this answer

edited Dec 12 '17 at 7:37

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I forgot to mention I don't have root access, will this still work? Also how does this script take in the userid as an argument? I need to check specific users.
  
  – linuxnewbie
  Dec 12 '17 at 1:56
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  To my understand the /var/spool/mail/ directory is a temporary directory that only holds unread mail. Once it is opened it is either deleted or moved to a different directory thats dedicated to the user. So I should be able to see if the user has unread mail in there just based off of the directory size. I'm just not sure if all of this adds up lol
  
  – linuxnewbie
  Dec 12 '17 at 1:59
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie, you only need x access to the directory to stat a file, and you have that anyway, since otherwise you couldn't reach your own mail spool file. Of course, as written, it doesn't take an argument, but that's not a very hard exercise (start here: [Tests and Conditionals])mywiki.wooledge.org/BashGuide/TestsAndConditionals) and the stat(1) man page). And sure, checking the size might be enough too. Depends on how the user works with their mailbox.
  
  – ilkkachu
  Dec 12 '17 at 7:42
  

  
  
  
  

add a comment | 

0

One method that is used to find unread mail is to check the timestamps on the mail spool file. If the file was written to after it was accessed (read), i.e. its mtime is greater than atime, then there is unread mail:

for f in /var/spool/mail/* ; do 
 [ $(stat -c '%Y -gt %X' "$f") ] && echo "$f has unread mail"
done

That of course considers everything in the mailbox as "read" after it's opened, regardless of if anyone looked at the individual messages.

In many cases, read messages are also moved away from the spool directory (to ~/mbox), so you could do with just checking the file size.

share|improve this answer

edited Dec 12 '17 at 7:37

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I forgot to mention I don't have root access, will this still work? Also how does this script take in the userid as an argument? I need to check specific users.
  
  – linuxnewbie
  Dec 12 '17 at 1:56
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  To my understand the /var/spool/mail/ directory is a temporary directory that only holds unread mail. Once it is opened it is either deleted or moved to a different directory thats dedicated to the user. So I should be able to see if the user has unread mail in there just based off of the directory size. I'm just not sure if all of this adds up lol
  
  – linuxnewbie
  Dec 12 '17 at 1:59
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @linuxnewbie, you only need x access to the directory to stat a file, and you have that anyway, since otherwise you couldn't reach your own mail spool file. Of course, as written, it doesn't take an argument, but that's not a very hard exercise (start here: [Tests and Conditionals])mywiki.wooledge.org/BashGuide/TestsAndConditionals) and the stat(1) man page). And sure, checking the size might be enough too. Depends on how the user works with their mailbox.
  
  – ilkkachu
  Dec 12 '17 at 7:42
  

  
  
  
  

add a comment | 

One method that is used to find unread mail is to check the timestamps on the mail spool file. If the file was written to after it was accessed (read), i.e. its mtime is greater than atime, then there is unread mail:

for f in /var/spool/mail/* ; do 
 [ $(stat -c '%Y -gt %X' "$f") ] && echo "$f has unread mail"
done

That of course considers everything in the mailbox as "read" after it's opened, regardless of if anyone looked at the individual messages.

In many cases, read messages are also moved away from the spool directory (to ~/mbox), so you could do with just checking the file size.

share|improve this answer

edited Dec 12 '17 at 7:37

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

for f in /var/spool/mail/* ; do 
 [ $(stat -c '%Y -gt %X' "$f") ] && echo "$f has unread mail"
done

share|improve this answer

edited Dec 12 '17 at 7:37

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172

answered Dec 12 '17 at 1:15

ilkkachuilkkachu

60.7k1098172