I'm trying to make a bash script that if a null value is returned then to output the value 0.
I would like a script to search the 'top' tree and return the CPU value of a process, however if the process is not running for it to return 0 or another identifier.
Any help appreciated.
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Working in a bash environment, in the following example, how do I direct the error message that putting in an invalid flag (-j for example) would normally produce to dev/null?
while getopts "abcd" opt
do
case "$opt" in
i) a etc ;;
r) b etc ;;
f) c etc ;;
v) d... (7 Replies)
Hi,
I have a shellscript that produces a csv that can be opened in Microsoft Excel. It has two columns and about 10 rows in each column, so only twenty cells (at the moment). When the user opened the csv, I wanted it so autofilter was already turned on in columns A1 and B1 (and potentially C1,... (1 Reply)
I have an input file having 7 fields delimited by ,
eg :
1,ABC,hg,1,2,34,3
2,hj,YU,2,3,4,
3,JU,kl,4,5,7,
4,JK,KJ,3,56,4,5
The seventh field here in some lines is empty, whereas the other lines there is a value.
How do I insert string NULL at this location (7th loc) for these lines where... (8 Replies)
I am testing some file routines against potential "nasty name" Unix files, such as those with a CR, LF, in the middle or NULL terminated, utf multi-byte character. So, under Bash, I want some way of:
mv "name" "name\0"
with the \0 a real NULL.
Against all my efforts, I have not been... (2 Replies)
Okay so i have a script i wrote in python. I want to turn this script into an INSTALLED COMMAND to run in terminal.
Right now i run it like this in terminal...
$ python myscriptname.py
or
$ ./myscriptname.py
but i want to be able to run it like this in terminal...
$ myscriptname
... (3 Replies)
Hi,
I was just helped with an excellent one liner. Now I need to know how to turn it into a script that I can call at the command line. So, this works with file script:
------------
for file in DATA.txt;
do
awk 'NR==1;NR>1{for (i=1;i<=NF;i++){a+=$i}}END{for (i=1;i<=NF;i++){printf... (3 Replies)
Hi everybody!
I am writing a script which accepts two arguments one of them being a message. All is working except for the message part. That is, to accept text as an argument.
I have trouble storing and echoing a line of text. It seems that writing a few words and store them in an... (6 Replies)
There are 4 parameters that I have to pass from korn shell to sql script.
1) I have to check if $1 , $2 , $3 and $4 are null values or not .
How can I do that ?
2) Once its determined that these values are null (in the sense they are empty) how can I pass null values to sql script... (11 Replies)
I have a shell script which select total count from a table and use its value in a if condition like below
connect_string="username/password@tnsname"
tot=`sqlplus -s $connect_string << EOF
set echo off
set feedback off
set head off
select count(*) from test_table;
EOF
`
if
then
echo... (2 Replies)
I'm new to utilities like socat and netcat and I'm not clear if they will do what I need.
I have a "compileDeployStartWebServer.sh" script and a "StartBrowser.sh" script that are started by emacs/elisp at the same time in two different processes.
I'm using Cygwin bash on Windows 10.
My... (3 Replies)
Discussion started by: siegfried
3 Replies
LEARN ABOUT CENTOS
script
SCRIPT(1) User Commands SCRIPT(1)NAME
script - make typescript of terminal session
SYNOPSIS
script [options] [file]
DESCRIPTION
script makes a typescript of everything printed on your terminal. It is useful for students who need a hardcopy record of an interactive
session as proof of an assignment, as the typescript file can be printed out later with lpr(1).
If the argument file is given, script saves all dialogue in file. If no file name is given, the typescript is saved in the file type-
script.
OPTIONS -a, --append
Append the output to file or typescript, retaining the prior contents.
-c, --command command
Run the command rather than an interactive shell. This makes it easy for a script to capture the output of a program that behaves
differently when its stdout is not a tty.
-e, --return
Return the exit code of the child process. Uses the same format as bash termination on signal termination exit code is 128+n.
-f, --flush
Flush output after each write. This is nice for telecooperation: one person does `mkfifo foo; script -f foo', and another can
supervise real-time what is being done using `cat foo'.
--force
Allow the default output destination, i.e. the typescript file, to be a hard or symbolic link. The command will follow a symbolic
link.
-q, --quiet
Be quiet.
-t, --timing[=file]
Output timing data to standard error, or to file when given. This data contains two fields, separated by a space. The first field
indicates how much time elapsed since the previous output. The second field indicates how many characters were output this time.
This information can be used to replay typescripts with realistic typing and output delays.
-V, --version
Output version information and exit.
-h, --help
Output help and exit.
NOTES
The script ends when the forked shell exits (a control-D to exit the Bourne shell (sh(1)), and exit, logout or control-d (if ignoreeof is
not set) for the C-shell, csh(1)).
Certain interactive commands, such as vi(1), create garbage in the typescript file. Script works best with commands that do not manipulate
the screen, the results are meant to emulate a hardcopy terminal.
ENVIRONMENT
The following environment variable is utilized by script:
SHELL If the variable SHELL exists, the shell forked by script will be that shell. If SHELL is not set, the Bourne shell is assumed.
(Most shells set this variable automatically).
SEE ALSO csh(1) (for the history mechanism), scriptreplay(1).
HISTORY
The script command appeared in 3.0BSD.
BUGS
Script places everything in the log file, including linefeeds and backspaces. This is not what the naive user expects.
AVAILABILITY
The script command is part of the util-linux package and is available from Linux Kernel Archive <ftp://ftp.kernel.org/pub/linux/utils/util-
linux/>.
util-linux September 2011 SCRIPT(1)