DUP(2) System Calls Manual DUP(2)NAME
dup, dup2 - duplicate an open file descriptor
SYNOPSIS
dup(fildes)
int fildes;
dup2(fildes, fildes2)
int fildes, fildes2;
DESCRIPTION
Given a file descriptor returned from an open, pipe, or creat call, dup allocates another file descriptor synonymous with the original.
The new file descriptor is returned.
In the second form of the call, fildes is a file descriptor referring to an open file, and fildes2 is a non-negative integer less than the
maximum value allowed for file descriptors (approximately 19). Dup2 causes fildes2 to refer to the same file as fildes. If fildes2
already referred to an open file, it is closed first.
SEE ALSO creat(2), open(2), close(2), pipe(2)DIAGNOSTICS
The value -1 is returned if: the given file descriptor is invalid; there are already too many open files.
ASSEMBLER
(dup = 41.)
(file descriptor in r0)
(new file descriptor in r1)
sys dup
(file descriptor in r0)
The dup2 entry is implemented by adding 0100 to fildes.
DUP(2)
Check Out this Related Man Page
dup2(3C) Standard C Library Functions dup2(3C)NAME
dup2 - duplicate an open file descriptor
SYNOPSIS
#include <unistd.h>
int dup2(int fildes, int fildes2);
DESCRIPTION
The dup2() function causes the file descriptor fildes2 to refer to the same file as fildes. The fildes argument is a file descriptor refer-
ring to an open file, and fildes2 is a non-negative integer less than the current value for the maximum number of open file descriptors
allowed the calling process. See getrlimit(2). If fildes2 already refers to an open file, not fildes, it is closed first. If fildes2
refers to fildes, or if fildes is not a valid open file descriptor, fildes2 will not be closed first.
The dup2() function is equivalent to fcntl(fildes, F_DUP2FD, fildes2).
RETURN VALUES
Upon successful completion a non-negative integer representing the file descriptor is returned. Otherwise, -1 is returned and errno is set
to indicate the error.
ERRORS
The dup2() function will fail if:
EBADF The fildes argument is not a valid open file descriptor.
EBADF The files2 argument is negative or is not less than the current resource limit returned by getrlimit(RLIMIT_NOFILE, ...).
EINTR A signal was caught during the dup2() call.
EMFILE The process has too many open files. See fcntl(2).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |Async-Signal-Safe |
+-----------------------------+-----------------------------+
SEE ALSO close(2), creat(2), exec(2), fcntl(2), getrlimit(2), open(2), pipe(2), lockf(3C), attributes(5), standards(5)SunOS 5.10 19 Dec 2003 dup2(3C)
I have a log file "logreport" that contains several lines as seen below:
04:20:00 /usr/lib/snmp/snmpdx: Agent snmpd appeared dead but responded to ping
06:38:08 /usr/lib/snmp/snmpdx: Agent snmpd appeared dead but responded to ping
07:11:05 /usr/lib/snmp/snmpdx: Agent snmpd appeared dead but... (18 Replies)
Hi All
This is not class assignment . I would like to know awk script how to
list all the duplicate name from a file ,have a look below
Sl No Name Dt of birth Location
1 aaa 1/01/1975 delhi
2 bbb 2/03/1977 mumbai
3 aaa 1/01/1976 mumbai
4 ... (22 Replies)
Can any one give me command How to delete duplicate records with out sort.
Suppose if the records like below:
345,bcd,789
123,abc,456
234,abc,456
712,bcd,789
out tput should be
345,bcd,789
123,abc,456
Key for the records is 2nd and 3rd fields.fields are seperated by colon(,). (19 Replies)
Hi All,
i have a zip file like the format
794051400123|COM|24|0|BD|R|99.98
794051413727|COM|11|0|BD|R|28.99
794051415622|COM|23|0|BD|R|28.99
883929004676|COM|0|0|BD|R|28.99
794051400123|MOM|62|0|BD|R|99.98
794051413727|MOM|4|0|BD|R|28.99
794051415622|MOM|80|0|BD|R|28.99
... (30 Replies)
Hello again, I am wanting to remove all duplicate blocks of XML code in a file. This is an example:
input:
<string-array name="threeItems">
<item>item1</item>
<item>item2</item>
<item>item3</item>
</string-array>
<string-array name="twoItems">
<item>item1</item>
<item>item2</item>... (19 Replies)
Hi
Ive been scratching over this for some time with no solution.
I have a file like this
1 bla bla 1
2 bla bla 2
4 bla bla 3
5 bla bla 1
6 bla bla 1
I want to remove consecutive occurrences of lines like bla bla 1, but the first column may be different.
Any ideasss?? (23 Replies)
Hi all,
I have an input file like this
Now
I have to remove duplicates only in first column and nothing has to be changed in second and third column. so that output would be
Please let me know scripting regarding this (20 Replies)
Gents,
I needs to delete duplicate values and only get uniq values based in columns 2-27
Always we should keep the last record found...
I need to store one clean file and other with the duplicate values removed.
Input :
S3033.0 7305.01 0 420123.8... (18 Replies)
I have a script that builds a database ~30 million lines, ~3.7 GB .cvs file. After multiple optimzations It takes about 62 min to bring in and parse all the files and used to take 10 min to remove duplicates until I was requested to add another column. I am using the highly optimized awk code:
awk... (34 Replies)
I have a BASH script that runs a continuous loop, reading a line from a file, and then spawning a background process to use it. I've placed "date" commands inside it to see where it's slowing down, and everything inside -- including reading the line from the file -- is fast, but the loop bogs... (34 Replies)
Within my text file i have several thousand lines of text with some lines containing duplicate strings/words. I would like to entirely remove those lines which contain the duplicate strings.
Eg;
One and a Two
Unix.com is the Best
This as a Line Line
Example duplicate sentence with the word... (22 Replies)
Gents,
Please give a help
file
--BAD STATUS NOT RESHOOTED--
*** VP 41255/51341 in sw 2973
*** VP 41679/51521 in sw 2973
*** VP 41687/51653 in sw 2973
*** VP 41719/51629 in sw 2976
--BAD COG NOT RESHOOTED--
*** VP 41689/51497 in sw 2974
*** VP 41699/51677 in sw 2974
*** VP... (18 Replies)
Dear forum members,
I want the script to count ALA as one (an example in quotes) and return an integer as 1 and not return 5 as an integer as it does now (look bash script). So how can I upgrade my script that it first checks or after finding all instances of ALA checks whether it is the same... (25 Replies)