You are right but I guess that this is just a typo and missing a 2nd adjacent & like marked bold here:
This works then like if the 1st who is successful, the command following will be executed, maybe to check if "who" itself is available and working. Sending "who" in the background and then following up the rest of commands would make no sense.
how can I find cpu usage memory usage swap usage and
I want to know CPU usage above X% and contiue Y times and memory usage above X % and contiue Y times
my final destination is monitor process
logical volume usage above X % and number of Logical voluage above
can I not to... (3 Replies)
Hi,
I have this line in a script:
if mt -f /dev/nst0 rewind > /tmp/status_nst0.log 2>&1 ; then
What does the 2>&1 mean? I think the line is saying that after rewinding the device if the log file does not exist then execute the code but I do not understand the contribution of the 2>&1.... (2 Replies)
Hi,
By using time command we can determine the execution time of a process or command.
bash-2.04$ time ls -l
total 0
-rw-r--r-- 1 admin tac 0 Oct 6 04:46 file1
-rw-r--r-- 1 admin tac 0 Oct 6 04:46 file2
real 0m0.002s
user 0m0.000s
sys 0m0.001s... (5 Replies)
Hi,
17 11 * * * /xx/yy/name.sh >> /tmp/cron.log 2>&1
The above statement is one of the crontab entries.
The crong log is getting appended everytime. Can anyone tell me the usage of "2>&1"?
Thanks. (2 Replies)
Hi all,
Can you please tell me the command, with which one can know the amount of space a specific directory has used.
df -k . ---> Displays, the amount of space allocated, and used for a directory.
du -k <dir name> - gives me the memory used of all the files inside <dir>
But i... (2 Replies)
In the terminal, using the ampersand allows the process to run in the background--Emacs, for example. But is there a way to automatically open Emacs as a background process so I can still use the command line? Typing the ampersand is just annoying to me, and I keep forgetting; it's just too useful... (0 Replies)
I have the following line of code that works wonders. I just don't completely understand it as I am just starting to learn regex. Can you help me understand exactly what is happening here?
find . -type f | grep -v '^\.$' | sed 's!\.\/!!' (4 Replies)
Hi all,
Been reading a lot of the cpu load and its "analogy of it to car traffic path of expressway"
From wiki
Most UNIX systems count only processes in the running (on CPU) or runnable (waiting for CPU) states. However, Linux also includes processes in uninterruptible sleep states... (13 Replies)
Hello everybody,
I have a Problem with sed command.
I want to replace a defined string with a string from a database field (dynamic).
e.g.
sed -i -e 's/%NAME%/'"$HNAME"'/g'
The Problem is that the $HNAME variable can contain Special characters like '&'
e.g.
HNAME="AH Kruger & Co. KG"
... (1 Reply)
For years I have spawned shell scripts with nohup and ampersand and they run whether or not I stay logged in. Recently a client told us that we had to set a keep alive timeout on all of our Redhat 7.6 Linux servers. Our sysadmin set the following parameters in the sshd_config file on all of our... (10 Replies)
Discussion started by: gandolf989
10 Replies
LEARN ABOUT DEBIAN
keyhead
keyhead(1) General Commands Manual keyhead(1)Name
keyhead - Change FITS or IRAF header keyword names
Synopsis
keyhead [-hknv] <FITS or IRAF file> kw1=kw1a kw2=kwd2a ... kwn=kwdna
Description
Change the names of keywords in FITS or IRAF image headers. Each current image keyword whose entry is to be modified should be followed by
an equal sign and a second keyword, with no intervening spaces. If the -r option is used, the value of the second keyword is transfered to
that of the first. Otherwise, the name of the first keyword is changed to the second keyword. To change keywords in a list of files, sub-
stitute @<listfile> for the file names on the command line. To change a lot of keywords, put them, one pair separated by an = sign with no
spaces per line, in a file and substitute @<keylistfile> on the command line. If two @ commands are present, the program will figure out
which contains file names and which contains keywords. Lines in a keyword list file which do not contain an = are ignored.
Options-h Write HISTORY line into output header with sethead version, current date and time, and names of keywords set.
-k Write KEYHEAD keyword into output header with the keyhead version, current date and time, and names of keywords whose names are
changed. If a KEYHEAD keyword already exists, move the old value to a HISTORY line before writing the new value
-n Write a new file with an added "e" before the extension.
-r letter
Replace value of 1st keyword with value of 2nd keyword instead of changing the name of the 1st keyword to the 2nd keyword. The 2nd
keyword remains in the header. If the 1st keyword does not exist in the header, it is created.
-v Print confirmations of each keyword change.
Web Page
http://tdc-www.harvard.edu/software/wcstools/keyhead.html
Author
Doug Mink, SAO (dmink@cfa.harvard.edu)
6 July 2001 WCSTools keyhead(1)