Not everyone has readlink. You can check the SHELL variable instead, it's quite standard.
Use [[ "$VAR1" == "value" ]] as single-equals and single square-braces are now archaic.
Automatically rerunning it with BASH is begging for an infinite loop if anything weird happens. You also didn't check if that exec failed.
Error messages should go to stderr, a la
Otherwise, people may find big flat error messages in their flatfiles whenever they redirect the output.
You don't need to and probably shouldn't be checking the text output of sudo -- just get its return value. There's also no reason to use a sub-shell, or a sub-sub-shell within that sub-shell. You can put it right into the if-statement as if it belongs there, which it does, with an ! in front to invert the return value.
I want develop a script which should also check validity of netmask.
e.g.
/etc/netmasks
10.15.20.30 255.255.255.224
How can I check which IP adresses are valid for this netmask?
I think the best is use logical operations.
224 is 1 1 1 0 0 0 0 0
so is valid from 10.15.20.31... (2 Replies)
I wish to seach a Dir for a specific file, once the file is found i will perform additional logic. If the file is not found within two hours, i would like to exit.
Logically, I'm looking for the best way to approach this
Thanks for any assistance in advance.
Note: I'm using a C shell and... (2 Replies)
I want to create an automated script which is called by another maually executed script.
The condition is that the no one should be able to manually execute the automated script.
The automated script can be on the same machine or it can be on a remote machine.
Can any one suggest a check in the... (1 Reply)
I have written the below script to determine whether a string is palindrome or not ?
But its not working, any help to debug it ?
I am new to this forum but when I searched for my question, I found that many people refused to answer this question thinking that its Homework question, Therefore I... (2 Replies)
please check this script and let me know.wher eis the issue.
#!/bin/ksh
set -A logs AAA BB CCC DDD EE FFF
set -A ltime 7 60 7 7 7 60
set i=1
while } ]
do
find /home/logs -name "*"\${logs}"\*.log" -mtime ${l
time} -type f -ls
let i=$i+1
done (3 Replies)
I have a local linux machine in which the files are dumped by a remote ubuntu server. If the process in remote server has any problem then empty files are created in local machine. Is there any way using perl script to check if the empty files are being created and delete them and then run a shell... (2 Replies)
Hi,
I am a unix newbie. I need to write a script to check wheteher another script is still running. If it is, then sleep for 30m and then check again if the script is running. If the script has stopped running then, I need to come out of the loop.
I am using RHEL 5.2 (2 Replies)
Hi guys,
I am sending the script i created..plzzz check it correct if any mistakes...:).
Plz reply early by today..
here i want to find the files based on date , if files are avaliable i want to send a mail to the user. here there are a total of 43 files. they are constant.
Here is... (0 Replies)
hi guys
we've had nagios spewing false alarm (for the umpteenth time) and finally the customer had enough so they're starting to question nagios. we had the check interval increased from 5 minutes to 2 minutes, but that's just temporary solution. I'm thinking of implementing a script on the... (8 Replies)
Discussion started by: hedkandi
8 Replies
LEARN ABOUT X11R4
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 displayed 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 the dialogue in this file. If no filename is given, the dialogue is saved in the file type-
script.
OPTIONS -a, --append
Append the output to file or to 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 (do not write start and done messages to standard output).
-t[file], --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
Display version information and exit.
-h, --help
Display help text and exit.
NOTES
The script ends when the forked shell exits (a control-D for 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.
It is not recommended to run script in non-interactive shells. The inner shell of script is always interactive, and this could lead to
unexpected results. If you use script in the shell initialization file, you have to avoid entering an infinite loop. You can use for
example the .profile file, which is read by login shells only:
if test -t 0 ; then
script
exit
fi
You should also avoid use of script in command pipes, as script can read more input than you would expect.
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.
script is primarily designed for interactive terminal sessions. When stdin is not a terminal (for example: echo foo | script), then the
session can hang, because the interactive shell within the script session misses EOF and script has no clue when to close the session. See
the NOTES section for more information.
AVAILABILITY
The script command is part of the util-linux package and is available from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils
/util-linux/>.
util-linux June 2014 SCRIPT(1)