hi,
I am a begginer in unix and i want to know how to open a file and read it and separate the numbers & words and storing it in separate files, Using shell scripting.
Please help me out for this.
Regards
S.Kamakshi (2 Replies)
Hi All,
I want to read one number from the file.
Only one number will be there in the file.
then i have to increment the number in my script and put it back in the same file.
Is it possible?
Can anybody help me?
Thanks,
Vinay (6 Replies)
Hi Guys,
I am new to unix.
Actually i want help in writing an single command where
i can actually read specific line number in file where the line number will be passed to command as parameter.
ex.
1 a
2 b
3 c
4 d
And to my command i pass as 2.
so i should get output as 2 b
... (15 Replies)
I have a file with a list of config files numbered on the lefthand side 1-300. I need to have bash read each lines number and assign it to a variable so it can be chosen by the user called by the script later.
Ex. 1 some data
2 something else
3 more stuff
which number do you... (1 Reply)
Hello, I'm trying to create a BASH file that can read all the files in my working directory and tell me how many words and lines are in that file. I wrote the following code:
FILES="*"
for f in "$FILES"
do
echo -e `wc -l -w $f`
done
My issue is that my file is outputting in one... (4 Replies)
Hello Everyone.
I am trying to display contains of a file from a specific line to a specific line(let say, from line number 3 to line number 5). For this I got the shell script as shown below:
if ; then
if ; then
tail +$1 $3 | head -n $2
else
... (5 Replies)
Hello All,
i am a newbie and need some help when reading a csv file in a bourne shell script. I want to read 10 lines, then wait for a minute and then do a reading of another 10 lines and so on in the same way. I want to do this till the end of file.
Any inputs are appreciated
... (3 Replies)
Hi all,
I have a file sample.txt
abc
asd
adf
daf
adw
add
adv
wdf
I want to control the number of lines to read
Like if i give input as ./script_name 2 5
required output
asd
adf
daf (2 Replies)
hello guys,
I'm struggled to get a number from a very long text file.
NAtoms= 33 NActive= 30 NUniq= 23 SFac= 1.00D+00 NAtFMM= 60 NAOKFM=F Big=F
Integral buffers will be 131072 words long.
Raffenetti 2 integral format.
The number 33 is what I wanted, always follows NAtoms=... (5 Replies)
I am new to ksh scripts. I would like to be able to read a file line by line from a certain line number. I have a specific line number saved in a variable, say $lineNumber. How can I start reading the file from the line number saved in $lineNumber? Thanks! (4 Replies)
Discussion started by: dcowboys13
4 Replies
LEARN ABOUT X11R4
pcap_dispatch
PCAP_LOOP(3PCAP)PCAP_LOOP(3PCAP)NAME
pcap_loop, pcap_dispatch - process packets from a live capture or savefile
SYNOPSIS
#include <pcap/pcap.h>
typedef void (*pcap_handler)(u_char *user, const struct pcap_pkthdr *h,
const u_char *bytes);
int pcap_loop(pcap_t *p, int cnt,
pcap_handler callback, u_char *user);
int pcap_dispatch(pcap_t *p, int cnt,
pcap_handler callback, u_char *user);
DESCRIPTION
pcap_loop() processes packets from a live capture or ``savefile'' until cnt packets are processed, the end of the ``savefile'' is reached
when reading from a ``savefile'', pcap_breakloop() is called, or an error occurs. It does not return when live read timeouts occur. A
value of -1 or 0 for cnt is equivalent to infinity, so that packets are processed until another ending condition occurs.
pcap_dispatch() processes packets from a live capture or ``savefile'' until cnt packets are processed, the end of the current bufferful of
packets is reached when doing a live capture, the end of the ``savefile'' is reached when reading from a ``savefile'', pcap_breakloop() is
called, or an error occurs. Thus, when doing a live capture, cnt is the maximum number of packets to process before returning, but is not
a minimum number; when reading a live capture, only one bufferful of packets is read at a time, so fewer than cnt packets may be processed.
A value of -1 or 0 for cnt causes all the packets received in one buffer to be processed when reading a live capture, and causes all the
packets in the file to be processed when reading a ``savefile''.
(In older versions of libpcap, the behavior when cnt was 0 was undefined; different platforms and devices behaved differently, so code that
must work with older versions of libpcap should use -1, nor 0, as the value of cnt.)
callback specifies a pcap_handler routine to be called with three arguments: a u_char pointer which is passed in the user argument to
pcap_loop() or pcap_dispatch(), a const struct pcap_pkthdr pointer pointing to the packet time stamp and lengths, and a const u_char
pointer to the first caplen (as given in the struct pcap_pkthdr a pointer to which is passed to the callback routine) bytes of data from
the packet. The struct pcap_pkthdr and the packet data are not to be freed by the callback routine, and are not guaranteed to be valid
after the callback routine returns; if the code needs them to be valid after the callback, it must make a copy of them.
RETURN VALUE
pcap_loop() returns 0 if cnt is exhausted, -1 if an error occurs, or -2 if the loop terminated due to a call to pcap_breakloop() before any
packets were processed. It does not return when live read timeouts occur; instead, it attempts to read more packets.
pcap_dispatch() returns the number of packets processed on success; this can be 0 if no packets were read from a live capture (if, for
example, they were discarded because they didn't pass the packet filter, or if, on platforms that support a read timeout that starts before
any packets arrive, the timeout expires before any packets arrive, or if the file descriptor for the capture device is in non-blocking mode
and no packets were available to be read) or if no more packets are available in a ``savefile.'' It returns -1 if an error occurs or -2 if
the loop terminated due to a call to pcap_breakloop() before any packets were processed. If your application uses pcap_breakloop(), make
sure that you explicitly check for -1 and -2, rather than just checking for a return value < 0.
If -1 is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to fetch or display the error text.
SEE ALSO pcap(3PCAP), pcap_geterr(3PCAP), pcap_breakloop(3PCAP)
24 December 2008 PCAP_LOOP(3PCAP)