It does not work that way. $(<file) is a special case, which is a faster alternative to $(cat file). If you are using anything other than just a file, it becomes something else. $( ... ) is just command sustitution, so if we leave out that, it becomes:
This is the same as tr -dc '[:alnum:],@#:!?+-' < /dev/urandom | head -c10
This is strange, it effectively just means cat /dev/urandom | head -c10
This is the same as the first one with UUOC
This is equivalent to :< /dev/urandom | tr -dc '[:alnum:],@#:!?+-' | head -c10, which is that same as : : | tr -dc '[:alnum:],@#:!?+-' | head -c10
This User Gave Thanks to Scrutinizer For This Post:
Can you use cat to send the first 25 lines of a file to the printer? I'm thinking I can pipe it with '|' but I'm not school to check printer output.
With the 'nl' used, all lines are numbered on the print out, but how does one number only the blank lines?
Thanks:) (1 Reply)
Hi,
I wnat to read a fiel line by line and store each line in a variabel, so I made a for loop:
for i in `cat file` ; do
#do sth.
done;
The problem is, that in the file, there are lines with only asterisks like this... (3 Replies)
Not sure how to do this exactly.. just want to take the first 100 lines of a file and cat it out into a second file. I know I can do a more on a file and > it into a different file, but how can I make it so only the first 100 lines get moved over? (1 Reply)
I want to cat a file with only show the line contain '/bin/bash' but don't show the line contain 'load' (don't show if the line contain 'load' and '/bin/bash' together), how to type in the command? thk a lot! (2 Replies)
I am looking for a command to take files with a specific date and cat them all into big file. I know I can use commands to list all of the files from a certain date. But I want to do that and take those files and make on large files containing all of them.
Any help would be great. This is being... (1 Reply)
Hi,
I have two files
one.txt
laptop
boy
apple
two.txt
unix
linux
OS
openS
I want to split one.txt into one line each and concatenate it with the two.txt
output files
onea.txt
laptop (4 Replies)
Hi All,
I have stumbled upon very unique issue. In my script I am doing cat file and then greping and cutting so as to assign the value to variable. My file is,
<mxc_tl_load_extractdata_prop.bsh>
DB_USER=test_oper
hostname=xxx
FTP_USER=test1_operate
MAIL_LIST=xxx@yyy.com... (1 Reply)
Hello,
I'm on a remote computer by SSH. How can I get the output of "cat file" into a file on the local computer?
I cannot use scp, because it's blocked.
something like:
ssh root@remote_maschine "cat /file" > /locale_machine/file
:rolleyes: (2 Replies)
Discussion started by: borsti007
2 Replies
LEARN ABOUT DEBIAN
flow-cat
flow-cat(1) General Commands Manual flow-cat(1)NAME
flow-cat -- Concatenate flow files
SYNOPSIS
flow-cat [-aghmp] [-b big|little] [-C comment] [-d debug_level] [-o filename] [-t start_time] [-T start_time] [-z z_level]
[file|directory ...]
DESCRIPTION
The flow-cat utility processes files and/or directories of files in the flow-tools format. The resulting concatenated data set is written
to the standard output or file specified by -o. If file is a single dash (`-') or absent, flow-cat will read from the standard input.
OPTIONS -a Do not ignore filenames that begin with tmp.
-b big|little
Byte order of output.
-C Comment
Add a comment.
-d debug_level
Enable debugging.
-g Sort file list by capture start time before processing.
-h Display help.
-m Disable the use of mmap().
-p Preload headers. Use to preserve meta information such as lost flows.
-o file Write to file instead of the standard out.
-t start_time
Select flow files up to start_time. If used with -T select files between start_time and end_time.
-T end_time
Select flow files after end_time. If used with -t select files between start_time and end_time.
-z z_level
Configure compression level to z_level. 0 is disabled (no compression), 9 is highest compression.
file|directory...
Process the files and/or directory.
TIME /DATE parsing
start_time and end_time parsing is implemented with getdate.y, a commonly used function to process free-form time date specifications.
Example usage borrowed from cvs:
1 month ago
2 hours ago
400000 seconds ago
last year
last Monday
yesterday
a fortnight ago
3/31/92 10:00:07 PST
January 23, 1987 10:05pm
22:00 GMT
EXAMPLES
Concatenate all flow files begining with ft-v05.2001-05.01, use flow-print to display the results.
flow-cat ft-v05.2001-05-01.* | flow-print
Concatenate flow files in /flows/krc4, store store the output in compressed.flows at compression level 9 (best). The headers are preloaded
so various metadata such as the flow count is correct in the result. Filenames begining with tmp which are typically in-progress flow
files from flow-capture are not processed.
flow-cat -p -z9 /flows/krc4 > compressed.flows
BUGS
None known.
AUTHOR
Mark Fullmer maf@splintered.net
SEE ALSO flow-tools(1)flow-cat(1)