Those API calls would be in section 2 of the manual: open/close/fopen/fclose/freopen
There is no the system file. There are many files necessary to create a working Unix system.
In Unix, the primary system calls for input and output are read(), write(), open(), close(), and lseek(). The open() call is used to open a file descriptor for reading or writing, while read() and write() perform the actual data transfer between the file descriptor and a buffer in memory. The close() call is used to close the file descriptor, and lseek() allows for repositioning the file pointer within the file. These calls provide a low-level interface for file and device I/O operations.
System calls provides interface use of services available in the operating system.
Douglas W. Topham has written: 'A system V guide to UNIX and XENIX' -- subject(s): UNIX System V (Computer file), XENIX (Computer file) 'The first book of UNIX' 'UNIX and XENIX' -- subject(s): UNIX (Computer file), XENIX
Information on the UNIX file system can be found in some magazines dedicated to technology such as Science Illustrated. Information can also be found on UNIX's official website.
Solaris employs the file system called UFS (UNIX file system) for its native file system type.
Root.
Rik Farrow has written: 'UNIX system security' -- subject(s): UNIX (Computer operating system), Computer security, UNIX (Computer file)
When a user logs in to a Unix system, the current working directory normally starts at the directory/file
The 'CD' command is not standard for Unix. The 'cd' command, however, will change directories (folders). It is a means of navigating the Unix file system.
There is no exact number because Unix systems vary. However, it is safe to say there are a lot of them, from hundreds to thousands..
It is a system software and all the processes in the operating system can be controlled by the user.