INTRO(7) Linux Programmer's Manual INTRO(7)NAME
intro - Introduction to overview, conventions, and miscellany section
DESCRIPTION
Section 7 of the manual provides overviews on various topics, and describes conventions and protocols, character set standards, the stan-
dard file system layout, and miscellaneous other things.
NOTES
Authors and Copyright Conditions
Look at the header of the manual page source for the author(s) and copyright conditions. Note that these can be different from page to
page!
SEE ALSO standards(7)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2007-10-23 INTRO(7)
Check Out this Related Man Page
INTRO(2) Linux Programmer's Manual INTRO(2)NAME
intro - Introduction to system calls
DESCRIPTION
Section 2 of the manual describes the Linux system calls. A system call is an entry point into the Linux kernel. Usually, system calls
are not invoked directly: instead, most system calls have corresponding C library wrapper functions which perform the steps required (e.g.,
trapping to kernel mode) in order to invoke the system call. Thus, making a system call looks the same as invoking a normal library func-
tion.
For a list of the Linux system calls, see syscalls(2).
RETURN VALUE
On error, most system calls return a negative error number (i.e., the negated value of one of the constants described in errno(3)). The C
library wrapper hides this detail from the caller: when a system call returns a negative value, the wrapper copies the absolute value into
the errno variable, and returns -1 as the return value of the wrapper.
The value returned by a successful system call depends on the call. Many system calls return 0 on success, but some can return nonzero
values from a successful call. The details are described in the individual manual pages.
In some cases, the programmer must define a feature test macro in order to obtain the declaration of a system call from the header file
specified in the man page SYNOPSIS section. In such cases, the required macro is described in the man page. For further information on
feature test macros, see feature_test_macros(7).
CONFORMING TO
Certain terms and abbreviations are used to indicate Unix variants and standards to which calls in this section conform. See standards(7).
NOTES
Calling Directly
In most cases, it is unnecessary to invoke a system call directly, but there are times when the Standard C library does not implement a
nice wrapper function for you. In this case, the programmer must manually invoke the system call using syscall(2). Historically, this was
also possible using one of the _syscall macros described in _syscall(2).
Authors and Copyright Conditions
Look at the header of the manual page source for the author(s) and copyright conditions. Note that these can be different from page to
page!
SEE ALSO _syscall(2), syscall(2), errno(3), feature_test_macros(7), standards(7)COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2010-02-03 INTRO(2)
Well, someone created a flash intro for us (their first attempt at SWiSH!)
OK,
SECOND DRAFT:
https://www.unix.com/test_intro2.swf
---------------------------
FIRST DRAFT:
https://www.unix.com/test_intro1.swf
Notice it says "Search before posting a question".....
Well????... (24 Replies)
Hi,
I have a doubt in introducing a delay in the programs.
We know that we do have a sleep() function/api using which
we can bring a delay in terms of seconds.
A minimum delay can be atleast 1 second.
Now I'm bothered about how to introduce a delay that is just
less than a second. Like... (3 Replies)
Hi all,
i would like to know how to introduce a delay in the execution of a cmd?
am trying to copy a file which is about 650 mb and then perform some actions on it..
however since its huge i would like to introduce a delay in exection until the process is over
i dont want it to proceed to... (10 Replies)
Hello, I'm only taking Intro to UNIX in school right now, so please bear with me. My problem is with a sort-of recycle-bin rig I've created for fun. I'm using Ubuntu 9.04, I am the admin. (only user, actually) of this computer. I'm using this script in ~/.bashrc
# if files exist, remove contents... (6 Replies)
Hello Experts,
I am new to this forum, I would like to do the following changes in one of the column of a txt file, which is having around 9 column.
For example, column 3 is having letters like this
AB11
AB12
C
CA
CB
AC1
AC2
I would like to convert the same column as follows
... (5 Replies)
Hi All,
How to introduce delay in the Bash/Shell Script till key stroke.
Below is the requirement..
1.Execute set of commands.
2.Display the message echo "press any key to continue"
Introduce a delay till key stroke.
3.Execute next set of commands.
Thanks in Advance
Sunil.K (5 Replies)
Hello,
To learn ZFS, i try to create pool .
and for that i want create 10 files with 512MB (because i dont have multiple disks and multiple controllers)
ADMIT THAT THIS IS TEN HIGH-PERFORMANCE HARD DRIVES
To get this 10 files,all of them have the same size : 512MB,
I do these... (9 Replies)
Dear Help,
I have an input file which looks like below
002 1000 2000 3000
003 2000 3000 4000
005 1000 2000 6000
I would like to have an output which inserts the missing number in sequential sorting as shown below...
001 0 0 0
002 1000 2000 3000
003 2000 3000 4000
004 0 0 0
005 1000... (5 Replies)
I am working with a log file that I am trying to clean up by removing non-English ASCII characters. I am using Bash via Cygwin on Windows.
Before I start I set:
export LC_ALL=C
I clean it up by removing all non-English ASCII characters with the following command;
grep -v $''... (4 Replies)
https://www.unix.com/members/1-albums212-picture687.png
Hunting Anomalous Bots - An Introduction to Cyber-Objects - Live From Cyberspace
Click title image (above) for video tutorial. (5 Replies)