Linking ulimit to /etc/security/limits.conf

fanoflq · 03-13-2017, 08:38 PM

I found discussion of ulimits in man bash.
But there is no mention of /etc/security/limits.conf.
So it is impossible for me to know it is related to ulimit.
Thank you Internet!

I like to figure out a way to use local host resources to
find out ulimit's companion config file,
/etc/security/limits.conf.

Where is limits.conf mentioned in man or any other docs?

Addendum:

Quote:

$ man -k limits.conf
limits.conf (5) - configuration file for the pam_limits module

From man limits.conf:
... ...
DESCRIPTION
The pam_limits.so module applies ulimit limits, nice priority and number of simultaneous login sessions limit to user login sessions. This description of the configuration file syntax applies to the /etc/security/limits.conf file and *.conf files in the /etc/security/limits.d directory.

sundialsvcs · 03-13-2017, 09:01 PM

Well, of course there is man ulimit which, as you know, covers "the basic command."

And, believe it or not, man limits.conf also works!

- - -

Now, let me explain.

Have a look at the output of this command: man man. (Yes: "the man-page about man itself.")

In the DESCRIPTION, you will see that man-pages are divided into multiple sections:

Code:

       1   Executable programs or shell commands
       2   System calls (functions provided by the kernel)
       3   Library calls (functions within program libraries)
       4   Special files (usually found in /dev)
       5   File formats and conventions eg /etc/passwd
       6   Games
       7   Miscellaneous (including macro packages and conventions), e.g. man(7), groff(7)
       8   System administration commands (usually only for root)
       9   Kernel routines [Non standard]

And, if you surf to a page such as limits.conf(5) - Linux man page ... "kindly notice that all-important business about '(5)'!"

This is a "section number."

If you omit the section-number, you'll get the manual-page for the first ... but only the first ... page where the requested term (such as "limits.conf") appears.
If you specify a section-number but get it wrong ... man 2 limits.conf ... you will fairly-rudely be told that there is "No manual entry for limits.conf in section 2"
"However, all is not lost!" The apropos command will tell you every man-page section where any particular keyword appears.

Ahem™ ...

Disclaimer: "this stuff made perfect sense in the late 1970's ..."
Full-disclosure disclaimer #2: "Bah! These kids today!" ... (koff koff™) ...

fanoflq · 03-13-2017, 09:33 PM

I incorrectly marked this solved
based on addendum in OP.

It is still difficult to link ulimit to
limits.conf since:

Quote:

$ man -k ulimit
fattach (2) - unimplemented system calls
ulimit (3) - get and set user limits

None of which have any reference to /etc/security/limits.conf!