I'm trying to answer the following question about file permissions in Unix. Consider a file with the following permissions:
rwx---r--
I am not the owner of this file, but I am a member of the group of this file.
My question is: do I have read access to this file?
I thought... (3 Replies)
Hello. I am trying to convert occurrences of 'NULL' from a datafile. The 'NULL' occurences appears at this:
|NULL| NULL|NULL| NULL|NULL| NULL|NULL| NULL|
There should be 52 fields per line.
I would like any occurrence of | NULL| or |NULL| to appear as '||'
Currently I am using this sed... (2 Replies)
Hi,
I'm in the midst of writing a UNIX script that sftp's files to an external host and am stuck with a problem. The problem is that the files created on my server as a order number that correlates to a sequence of directories on the remote host which is where the file should be ftp'ed.
... (3 Replies)
Hi,
I am at a point in my script where I defined the number of the command line parameter I would like to set a variable equal to:
parameter_number=14
I would then like to set a variable equal to the correct parameter:
variable=$parameter_number
The issue here is that {} is required... (2 Replies)
This post is in reference to https://www.unix.com/shell-programming-scripting/137977-tricky-sed-awk-question-post302428154.html#post302428154
I am trying to go the opposite direction now:
I have the following file:
a,b,C,f,g
a,b,D,f,g
a,b,E,f,g
h,i,J,k,l
m,n,O,t,u
m,n,P,t,u
m,n,Q,t,u... (3 Replies)
Hi,
I have a file which contains two strings: AAAAA and BBBBB
I have two variables in my script:
DATE="03/21/2010"
aDate="20100321"
I need to replace string AAAAA with variable $DATE and BBBBB with $aDate. Here is what I do
sed "s/AAAAA/$DATE/" $BASIC_TMPLT | sed "s/BBBBB/$aDate/" >... (4 Replies)
I have some large login files that I need to extract (user)@(server) from. Where it gets tricky is that there is usually more than one '@' sign on each line(although it does have a leading space if it's not part of the (user)@(server) string), I need only the (user)@(server) section, I need only... (6 Replies)
I have some data files that I can identify by a certain pattern in the names using find.
Every one of those data files has an XML file associated with it (can be multiple data files per XML file).
The XML file is always up one directory from the data file(s) in a folder calledRun##### -... (12 Replies)
Hi All
I need to put some sed together for a task and its a bit advanced for me, so I thought I'd ask if anyone here could help.
I have a csv file with content like this -
"","abcde","",""
"'","abcde","",""
"","","","1234"
"'e'","","",""
I need to remove any single quotes that fall... (17 Replies)
Discussion started by: steadyonabix
17 Replies
LEARN ABOUT OSX
env5.12
Env(3pm) Perl Programmers Reference Guide Env(3pm)NAME
Env - perl module that imports environment variables as scalars or arrays
SYNOPSIS
use Env;
use Env qw(PATH HOME TERM);
use Env qw($SHELL @LD_LIBRARY_PATH);
DESCRIPTION
Perl maintains environment variables in a special hash named %ENV. For when this access method is inconvenient, the Perl module "Env"
allows environment variables to be treated as scalar or array variables.
The "Env::import()" function ties environment variables with suitable names to global Perl variables with the same names. By default it
ties all existing environment variables ("keys %ENV") to scalars. If the "import" function receives arguments, it takes them to be a list
of variables to tie; it's okay if they don't yet exist. The scalar type prefix '$' is inferred for any element of this list not prefixed by
'$' or '@'. Arrays are implemented in terms of "split" and "join", using $Config::Config{path_sep} as the delimiter.
After an environment variable is tied, merely use it like a normal variable. You may access its value
@path = split(/:/, $PATH);
print join("
", @LD_LIBRARY_PATH), "
";
or modify it
$PATH .= ":.";
push @LD_LIBRARY_PATH, $dir;
however you'd like. Bear in mind, however, that each access to a tied array variable requires splitting the environment variable's string
anew.
The code:
use Env qw(@PATH);
push @PATH, '.';
is equivalent to:
use Env qw(PATH);
$PATH .= ":.";
except that if $ENV{PATH} started out empty, the second approach leaves it with the (odd) value "":."", but the first approach leaves it
with ""."".
To remove a tied environment variable from the environment, assign it the undefined value
undef $PATH;
undef @LD_LIBRARY_PATH;
LIMITATIONS
On VMS systems, arrays tied to environment variables are read-only. Attempting to change anything will cause a warning.
AUTHOR
Chip Salzenberg <chip@fin.uucp> and Gregor N. Purdy <gregor@focusresearch.com>
perl v5.12.5 2012-11-03 Env(3pm)