apologies, I didn't explain that well. We get multiple B* files from the banks and the names of the actual B* file changes. However one of the B* files now references two accounts/groups in that file. We want to delete the content of the 2nd account of that original file without changing the name of the original file.
we are wanting to delete lines of texts from one of those B* files . but we cant always say its an exact line number. the /^999-999/d seems to work for deleting that whole line any other lines starting with that reference number.
if I run the following manually it looks ok from the unix prompt
it seems to work, but I don't know how to save it. I tried the $i after the delete as the name but the file didn't save the removed part.
Last edited by Don Cragun; 07-28-2015 at 11:17 PM..
Reason: Add CODE tags.
Hi gurus,
I have this file with blank lines in it.
How do i remove them in shell?
I tried these commands but not working:
sed '/^ *$/d'
or
sed '/^$/d'
Anybody has a better idea pls?
Also there are lines which starts with a single space, how do we remove the space in those lines?... (3 Replies)
Hi,
I am writing a shell script that needs to remove duplicate lines within a file by category.
example:
section a
a
c
b
a
section b
a
b
a
c
I need to remove the duplicates within th category with out removing the duplicates from the 2 different sections (one of the a's in section... (1 Reply)
Hi,
There seems to some hack attempts in my site. I have attached the index page of my site and I need to remove the below lines from the index page. The below lines are at the center of the file.
-->
</style>
<script>E V A L( unescape(... (5 Replies)
hi,,
i hav a file with many lines.i need to remove all lines before a line begginning with a specific pattern from the file because these lines are not required.
Can u help me out with either a perl script or shell script
example:-
if file initially contains lines:
a
b
c
d
.1.2
d
e
f... (2 Replies)
A small question
I have a test.txt file
I have contents as:
a:google
b:yahoo
:
c:facebook
:
d:hotmail
How do I remove the line with :
my output should be
a:google
b:yahoo
c:facebook
d:hotmail (5 Replies)
Hi,
I have a huge file which has Lacs of lines. File system got full.
I want your guys help to suggest me a solution so that I can remove all lines from that file but not last 50,000 lines. I want solution which can remove lines from existing file so that I can have some space left with. (28 Replies)
Please Help (novice to PERL and SHELL scripting)…. Need to create a script which removes all lines in $filename = "cycle_calendar_ftp_out" older than current date – a variable which will be a number of days passed to script. For Ex it will look at the end date which is the last field (4) and... (2 Replies)
Hello everyone,
Although it seems easy, I've been stuck with this problem for a moment now and I can't figure out a way to get it done.
My problem is the following:
I have a file where each line is a sequence of IP addresses, example :
10.0.0.1 10.0.0.2
10.0.0.5 10.0.0.1 10.0.0.2... (5 Replies)
Hello,
I have a SAS code that predominantly has comments line and the real code like below and i want to remove ONLY THE COMMENTS from the code in the single line or spanned across multiple lines.
/********************************************************************
*** This Is a Comment... (4 Replies)
Discussion started by: arooonatr
4 Replies
LEARN ABOUT POSIX
chpasswd
CHPASSWD(8) System Management Commands CHPASSWD(8)NAME
chpasswd - update passwords in batch mode
SYNOPSIS
chpasswd [options]
DESCRIPTION
The chpasswd command reads a list of user name and password pairs from standard input and uses this information to update a group of
existing users. Each line is of the format:
user_name:password
By default the passwords must be supplied in clear-text, and are encrypted by chpasswd. Also the password age will be updated, if present.
By default, passwords are encrypted by PAM, but (even if not recommended) you can select a different encryption method with the -e, -m, or
-c options.
Except when PAM is used to encrypt the passwords, chpasswd first updates all the passwords in memory, and then commits all the changes to
disk if no errors occurred for any user.
When PAM is used to encrypt the passwords (and update the passwords in the system database) then if a password cannot be updated chpasswd
continues updating the passwords of the next users, and will return an error code on exit.
This command is intended to be used in a large system environment where many accounts are created at a single time.
OPTIONS
The options which apply to the chpasswd command are:
-c, --crypt-method METHOD
Use the specified method to encrypt the passwords.
The available methods are DES, MD5, NONE, and SHA256 or SHA512 if your libc support these methods.
By default, PAM is used to encrypt the passwords.
-e, --encrypted
Supplied passwords are in encrypted form.
-h, --help
Display help message and exit.
-m, --md5
Use MD5 encryption instead of DES when the supplied passwords are not encrypted.
-R, --root CHROOT_DIR
Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory.
-s, --sha-rounds ROUNDS
Use the specified number of rounds to encrypt the passwords.
The value 0 means that the system will choose the default number of rounds for the crypt method (5000).
A minimal value of 1000 and a maximal value of 999,999,999 will be enforced.
You can only use this option with the SHA256 or SHA512 crypt method.
By default, the number of rounds is defined by the SHA_CRYPT_MIN_ROUNDS and SHA_CRYPT_MAX_ROUNDS variables in /etc/login.defs.
CAVEATS
Remember to set permissions or umask to prevent readability of unencrypted files by other users.
CONFIGURATION
The following configuration variables in /etc/login.defs change the behavior of this tool:
SHA_CRYPT_MIN_ROUNDS (number), SHA_CRYPT_MAX_ROUNDS (number)
When ENCRYPT_METHOD is set to SHA256 or SHA512, this defines the number of SHA rounds used by the encryption algorithm by default (when
the number of rounds is not specified on the command line).
With a lot of rounds, it is more difficult to brute forcing the password. But note also that more CPU resources will be needed to
authenticate users.
If not specified, the libc will choose the default number of rounds (5000).
The values must be inside the 1000-999,999,999 range.
If only one of the SHA_CRYPT_MIN_ROUNDS or SHA_CRYPT_MAX_ROUNDS values is set, then this value will be used.
If SHA_CRYPT_MIN_ROUNDS > SHA_CRYPT_MAX_ROUNDS, the highest value will be used.
Note: This only affect the generation of group passwords. The generation of user passwords is done by PAM and subject to the PAM
configuration. It is recommended to set this variable consistently with the PAM configuration.
FILES
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
/etc/login.defs
Shadow password suite configuration.
/etc/pam.d/chpasswd
PAM configuration for chpasswd.
SEE ALSO passwd(1), newusers(8), login.defs(5), useradd(8).
shadow-utils 4.5 01/25/2018 CHPASSWD(8)