Oracle Linux 5.6, 64-bit
Given the following snippet
Code:
wrkvar=`sqlplus -s / as sysdba <<EOF
set echo off feedback off head off trimsp on
select count(*) from v\$parameter
where name in ('db_file_name_convert','log_file_name_convert')
and value is not null;
EOF`
echo wrkvar=$wrkvar
Produces the following results
Code:
wrkvar=select count(*) from v db_refresh db_refresh.sav doit ERROR at line 1: ORA-00942: table or view does not exist
Whereas taking the entire sqlplus block out of the command substitution (just executing it) runs as expected. Also, using the other method of command substitution works as expected:
Code:
wrkvar=$(sqlplus -s / as sysdba <<EOF
set echo off feedback off head off trimsp on
select count(*) from v\$parameter
where name in ('db_file_name_convert','log_file_name_convert')
and value is not null;
EOF)
echo wrkvar=$wrkvar
produces
Code:
wrkvar= 2
It would appear that something about the first variant doesn't like the escaping of the $ (v\$parameter). Obviously a gap in my understanding ...
"Is there any substituation of last command or script syntax which can be used as a user. As far I know the "last" command is being used to display information about previous logins. A member of adm group or the user adm can execute it only.
Thanks in advance for your usual help.
Ghazi (6 Replies)
hi,
I have to execute this line below from within a shell script; simply backquoting it is not doing the trick; it is mangling up all the options; but when i type it out on a command line, it executes cleanly. Please help me in getting this right;
$ vlc -I dummy --sout='#transcode{vcodec=mp4v,... (5 Replies)
Hi,
What is the actual difference between these two? Why the following code works for process substitution and fails for command substitution?
while IFS= read -r line; do echo $line; done < <(cat file)executes successfully and display the contents of the file
But,
while IFS='\n' read -r... (3 Replies)
I'm trying to get this to work and I'm not really sure how to do it.
echo $x | awk '{print $NF}' MODIFIEDThe output I'm trying to get should look like:
dir1 MODIFIED
Where dir1 will be the result of:
$x |awk '{print $NF}'I'm sure there's something I'm supposed to put around that part... (3 Replies)
I know this script is crummy, but I was just messing around.. how do I get sed's insert command to allow variable expansion to show the filename?
#!/bin/bash
filename=`echo $0`
/usr/bin/sed '/#include/ {
i\
the filename is `$filename`
}' $1
exit 0 (8 Replies)
Hey, guys!
Trying to research this is such a pain since the read command itself is a common word. Try searching "unix OR linux read command examples" or using the command substitution keyword. :eek:
So, I wanted to use a command statement similar to the following.
This is kinda taken... (2 Replies)
Hello Folks,
how to write a command on vi that allow to repeat last substitution command?
Here what I want to do :
1
2
3
1
2
3
1
2
3
:.,+2s/\n/ /And I obtain :
1 2 3
1
2
3
1 (5 Replies)
Hi,
I want to know if there's a cleaner way for assigning output of a unix command to a variable in C program .
Example : I execute dirname fname and want the output to be assigned to a variable dname . Is it possible .
I knew u can redirect the output to a file and then reread assigning... (5 Replies)
a=1
b1=unix
echo $b`$a`
The above code is not working. Instead of printing the variable b1 using 'echo $b1', how to use variable 'a' to print 'b1' (1 Reply)
I have the following code:
strfuture=abcdefghi
ver=${strfuture:${count}:1}
mj7777_ver=${ver} start_mj7777_iteration
let count=count+1
When it is executed I get bad substitution. The same if I use
ver=${strfuture:$count:1}
mj7777_ver=${ver}... (6 Replies)
Discussion started by: Bruble
6 Replies
LEARN ABOUT REDHAT
ppmtosixel
ppmtosixel(1) General Commands Manual ppmtosixel(1)NAME
ppmtosixel - convert a portable pixmap into DEC sixel format
SYNOPSIS
ppmtosixel [-raw] [-margin] [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces sixel commands (SIX) as output. The output is formatted for color printing, e.g. for a DEC
LJ250 color inkjet printer.
If RGB values from the PPM file do not have maxval=100, the RGB values are rescaled. A printer control header and a color assignment table
begin the SIX file. Image data is written in a compressed format by default. A printer control footer ends the image file.
OPTIONS -raw If specified, each pixel will be explicitly described in the image file. If -raw is not specified, output will default to com-
pressed format in which identical adjacent pixels are replaced by "repeat pixel" commands. A raw file is often an order of magni-
tude larger than a compressed file and prints much slower.
-margin
If -margin is not specified, the image will be start at the left margin (of the window, paper, or whatever). If -margin is speci-
fied, a 1.5 inch left margin will offset the image.
PRINTING
Generally, sixel files must reach the printer unfiltered. Use the lpr -x option or cat filename > /dev/tty0?.
BUGS
Upon rescaling, truncation of the least significant bits of RGB values may result in poor color conversion. If the original PPM maxval was
greater than 100, rescaling also reduces the image depth. While the actual RGB values from the ppm file are more or less retained, the
color palette of the LJ250 may not match the colors on your screen. This seems to be a printer limitation.
SEE ALSO ppm(5)AUTHOR
Copyright (C) 1991 by Rick Vinci.
26 April 1991 ppmtosixel(1)
04-09-2014
