When I type 'man read' on shell prompt it displays read shell command, how do I open documentation for read() C function. My question is not just for read applies to similar other functions like sleep()
I usually run to https://linux.die.net when it happens and refer documentation there, I am sure there would be way to get to right man page from shell prompt itself
man <section #> <page>
From the man man page:
The table below shows the section numbers of the manual followed by the types of pages they contain.
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]
To look up what sections exist for a given page, you can use the -k flag:
$ man -k ^sleep$
sleep (1) - delay for a specified amount of time
sleep (3) - sleep for a specified number of seconds