Is it possible to use a file containing filters as a filter itself? Instead of having to write each filter -f ...... -f ....... have a file that contains all the filters I wish to use to capture? What should the format of this file be? How do I create said file? "Filter1" udp "Filter2" ip6 ........ When using this file using CMD what would the expression be? dumpcap -i 5 -???????? -w capture.pcapng
I expect an expression of what to type in CMD in order to use a file as a capture filter instead of manually writing all filters as -f ........ -f .......
Related
I am trying to check whether variable GROUP exist in SAS data set file or not from the UNIX command but unfortunately it's showing that GROUP variable does not exist in the data set,However GROUP variable is present in SAS data set.
In my command for case sensitive and whole word match I am using i and w options of grep command respectively. But still UNIX command is not giving the expected result.I s there any way to fix this issue?
Below is the command which I am using:
sasfile="sasdata"
rwords="GROUP"
cat $sasfile | grep -iqw "$rwords"
Thank you
As mentioned in earlier comment
SAS data sets are stored in disk files using a proprietary format.
There may be encodings and storage methodologies that do not yield the
information you seek in a plain text examination of said disk file.
Running SAS code in a SAS session is the definitive way to glean information about a data set.
What will that code look like ?
Proc CONTENTS
Data step or macro code that uses VARNAME function
... many other ways ...
In UNIX SAS can use stdio.
From "SAS(R) 9.2 Companion for UNIX Environments", STDIO System Option: UNIX
Details
This option tells SAS to take its input from standard input (stdin),
to write its log to standard error (stderr), and to write its output
to standard output (stdout).
This option is designed for running SAS
in batch mode or from a shell script. If you specify this option
interactively, SAS starts a line mode session.
The STDIO option
overrides the DMS, DMSEXP, and EXPLORER system options. The STDIO
option does not affect the assignment of the Stdio, Stdin, and Stderr
filerefs. See Filerefs Assigned by SAS in UNIX Environments for more
information.
For example, in the following SAS command, the file
myinput is used as the source program, and files myoutput and mylog
are used for the procedure output and log respectively.
sas -stdio < myinput > myoutput 2> mylog
If you are using the C shell, you should
use parentheses:
(sas -stdio < myinput > myoutput ) >& output_log
With -stdio you want a short SAS program that can indicate if a variable is present in a data set, or perhaps emit a list of variables in a data set for further shell processing. A Proc CONTENTS step is short and sweet.
So looking for your proverbial needle in a haystack
sasfile=<path to data set file>/<dataset>.sas7bdat
needle=GROUP
echo "Proc CONTENTS data=""$sasfile""" | sas -stdio | grep $needle
The default CONTENTS output might contain yield some false matches. So you could also try
echo "Proc CONTENTS noprint data=""$sasfile"" out=list;data _null_;set list;file print;put name;"
| sas -stdio
| grep -i "GROUP"
You could try:
sasfile="sasdata"
rwords="GROUP"
grep -iw "$rwords" "$sasfile"
The only difference between these and your original commands is that I omitted cat and grep's quiet flag -q.
Sample input in sasdata:
fasd group
fdsfds fdsfdsa
fdsfd as GROUP afdsfdsa
Output:
fasd group
fdsfd as GROUP afdsfdsa
The -q flag of grep will suppress standard output but echo $? can retrieve the return value of grep. Using the same input file as before:
grep -iqw "$rwords" "$sasfile" # No stout
echo $? # Prints 0, means grep succeeded
grep -iqw "word" "$sasfile" # No stout
echo $? # Prints 1, means grep failed
I am running a grep command on each file in a directory. I want the outputs to be appended into the same file. Is this possible?
Here is what I am using unsuccessfully:
for f in /directory/*.txt
do
grep -Eo "[0-9]+\.[0-9]+" $f >> one_output_file.txt
done
I am grepping out a number from each file and I want the numbers to be listed together in ONE output file. Possible?
Thanks!
Why not drop the for loop and do
grep -Eoh "[0-9]+\.[0-9]+" /directory/*.txt > one_output_file.txt
So I can add a link to a debug symbol file like this objcopy --add-gnu-debuglink=$name.dbg $name, but how can I later retrieve that value again?
I checked with readelf -a and grepped for \.dbg without any luck. Similarly I checked the with objdump -sj .gnu_debuglink (.gnu_debuglink is the section) and could see the value there:
$ objdump -sj .gnu_debuglink helloworld|grep \.dbg
0000 68656c6c 6f776f72 6c642e64 62670000 helloworld.dbg..
However, would there be a command that allows me to extract the retrieve the exact value again (i.e. helloworld.dbg in the above example)? That is the file name only ...
I realize I could use some shell foo here, but it seems odd that an option exists to set this value but none to retrieve it. So I probably just missed it.
You can use readelf directly:
$ readelf --string-dump=.gnu_debuglink helloworld
String dump of section '.gnu_debuglink':
[ 0] helloworld
[ 1b] 9
I do not know what the second entry means (it seems to always be different). To get rid of the header and the offsets, you can use sed:
$ readelf --string-dump=.gnu_debuglink helloworld | sed -n '/]/{s/.* //;p;q}'
helloworld
Something like this should work:
objcopy --output-target=binary --set-section-flags .gnu_debuglink=alloc \
--only-section=.gnu_debuglink helloworld helloworld.dbg
--output-target=binary avoids adding ELF headers. --set-section-flags .gnu_debuglink=alloc is needed because objcopy only writes allocated sections by default (with the binary emulation). And --only-section=.gnu_debuglink finally identifies the answer. See this earlier answer.
Note that the generated file may have a trailing NUL byte and four bytes of CRC, so some post-processing is needed to extract everything up to the first NUL byte (perhaps using head -z -n 1 helloworld.dbg | tr -d '\0' or something similar).
SAXON 6.5.4 from Michael Kay
Usage: java com.icl.saxon.StyleSheet [options] source-doc style-doc {param=value}...
Options:
-a Use xml-stylesheet PI, not style-doc argument
-ds Use standard tree data structure
-dt Use tinytree data structure (default)
-o filename Send output to named file or directory
-m classname Use specified Emitter class for xsl:message output
-r classname Use specified URIResolver class
-t Display version and timing information
-T Set standard TraceListener
-TL classname Set a specific TraceListener
-u Names are URLs not filenames
-w0 Recover silently from recoverable errors
-w1 Report recoverable errors and continue (default)
-w2 Treat recoverable errors as fatal
-x classname Use specified SAX parser for source file
-y classname Use specified SAX parser for stylesheet
-? Display this message
If your stylesheet declares a parameter
<xsl:param name="iridescent"/>
Then you can set it from the command line with (for example)
java com.icl.saxon.Stylesheet source.xml style.xsl iridescent=no
I'm running a ffmpeg command to try to get the duration of a video file, the command is as follows...
system('ffmpeg -i C:\Users\example\Desktop\video9.mp4 -f ffmetadata')
When I run that line it outputs a lot of info to the rails console, including duration. But how would I capture that info so I can split it and grab the data I need? (I'm doing this inside a rails controller)
When I run something like this...
metadata = system('ffmpeg -i C:\Users\example\Desktop\video9.mp4 -f ffmetadata')
puts metadata
All it returns is false.
Use:
output = `ffmpeg -i C:\\Users\\example\\Desktop\\video9.mp4 -f ffmetadata`
The problem is that system doesn't capture the output of the command being run. Instead, we use %x[...] or its equivalent using backticks, which captures the sub-shell's STDOUT.
If you need more control, look at Open3.capture3.
Found it...
inspect_command = "ffmpeg -i " + file_location + " 2>&1 "
metadata = `#{inspect_command}`
If all you need to get is the video duration use ffprobe instead of ffmpeg. It returns the video metadata directly.