sed processes files line-by-line - the 'g' option refers to instances of the pattern on the addressed line(s), not the whole file.
If you want to restrict the substitution to parts of the input file you'll need to supply an address, e.g.:
(addresses from line 0 to the first instance of abc)
Hello.
Consider the following magic words:
# ls `which adduser`
ls: /usr/sbin/adduser: No such file or directory
#
Hmmm...
Then:
# ls /usr/sbin/adduser
/usr/sbin/adduser
#
Now what?
Unforunately this little sniippet is used in my debian woody server's mysql pre install script.... (2 Replies)
Hi,
I use the command
ls a\b\c\*.txt
from the command line on HP UNIX and it works fine - It lists all files matching *.txt in the a\b\c directory
When embeded in a ksh script
`ls a\b\c\*.txt`
it does not work - I get *.txt not found (even though there are files)
I tried... (10 Replies)
Portion of my script below :
if ; then
NUMBEROFFEILDS=`cat ${BASE_SCRIPT_LOC}/standardfilecleanup.lst|grep -w ${db_file_path}|awk -F: '{print NF}'`
COUNT=4
while ; do
awk_var="$"`echo $COUNT`
file_name1=`cat ${BASE_SCRIPT_LOC}/standardfilecleanup.lst|grep -w... (1 Reply)
I am trying to find only those entries where 7018 and another number appear in the end of the line.
7018 2828 1423 2351
7018 2828 14887
2828 7018 1222
123 7018 1487
I am looking for a way to generate only the last two lines. I was trying to do just "grep '7018{1,5}" but it does not... (5 Replies)
Hi!
Been working on a script and I've been having a problem. I've finally narrowed it down to this variable I'm setting:
servername=$(awk -v FS=\/ '{ print $7 } blah.txt | sed 's\/./-/g' | awk -v FS=\- '{print $1}')"
This will essentially pare down a line like this:
... (7 Replies)
I need to sort through a volume that contains video files by access time and delete files that have not been accessed over x days. I have to use the access time as video files are originals that do not get modified, just read
Testing commands on a local test folder...
$ date
Wed Sep 28... (10 Replies)
Hi. I am trying to start a script on my router that will execute even if i log off. To execute the script I write:
nohup ./dslconnection > dslstat.out 2>&1 &
It starts the job:
21968 admin 1604 S /bin/ash ./dslconnection
The problem is that when I log back in the job has been... (6 Replies)
Hi,
I have prepared a script and trying to execute it but not getting expected output. Could you please help and advise what is going wrong.
"If else" part in below script is not working basically.
I am running it on HP-UX.
for i in slpd puma sfmdb
do
echo "******\t$i\t*******"
echo... (10 Replies)
I ran into the following and still do not understand entirely the rationale behind this. If someone could explain why things are as they are I'd be thankful.
The following was tested on AIX 7.1 with ksh88, but i suspect that to be ubiquitous. In an installation routine i had to create a set of... (6 Replies)
Discussion started by: bakunin
6 Replies
LEARN ABOUT OSX
subst
subst(n) Tcl Built-In Commands subst(n)
__________________________________________________________________________________________________________________________________________________NAME
subst - Perform backslash, command, and variable substitutions
SYNOPSIS
subst ?-nobackslashes? ?-nocommands? ?-novariables? string
_________________________________________________________________DESCRIPTION
This command performs variable substitutions, command substitutions, and backslash substitutions on its string argument and returns the
fully-substituted result. The substitutions are performed in exactly the same way as for Tcl commands. As a result, the string argument
is actually substituted twice, once by the Tcl parser in the usual fashion for Tcl commands, and again by the subst command.
If any of the -nobackslashes, -nocommands, or -novariables are specified, then the corresponding substitutions are not performed. For
example, if -nocommands is specified, command substitution is not performed: open and close brackets are treated as ordinary characters
with no special interpretation.
Note that the substitution of one kind can include substitution of other kinds. For example, even when the -novariables option is speci-
fied, command substitution is performed without restriction. This means that any variable substitution necessary to complete the command
substitution will still take place. Likewise, any command substitution necessary to complete a variable substitution will take place, even
when -nocommands is specified. See the EXAMPLES below.
If an error occurs during substitution, then subst will return that error. If a break exception occurs during command or variable substi-
tution, the result of the whole substitution will be the string (as substituted) up to the start of the substitution that raised the excep-
tion. If a continue exception occurs during the evaluation of a command or variable substitution, an empty string will be substituted for
that entire command or variable substitution (as long as it is well-formed Tcl.) If a return exception occurs, or any other return code is
returned during command or variable substitution, then the returned value is substituted for that substitution. See the EXAMPLES below.
In this way, all exceptional return codes are "caught" by subst. The subst command itself will either return an error, or will complete
successfully.
EXAMPLES
When it performs its substitutions, subst does not give any special treatment to double quotes or curly braces (except within command sub-
stitutions) so the script
set a 44
subst {xyz {$a}}
returns "xyz {44}", not "xyz {$a}" and the script
set a "p} q {r"
subst {xyz {$a}}
returns "xyz {p} q {r}", not "xyz {p} q {r}".
When command substitution is performed, it includes any variable substitution necessary to evaluate the script.
set a 44
subst -novariables {$a [format $a]}
returns "$a 44", not "$a $a". Similarly, when variable substitution is performed, it includes any command substitution necessary to
retrieve the value of the variable.
proc b {} {return c}
array set a {c c [b] tricky}
subst -nocommands {[b] $a([b])}
returns "[b] c", not "[b] tricky".
The continue and break exceptions allow command substitutions to prevent substitution of the rest of the command substitution and the rest
of string respectively, giving script authors more options when processing text using subst. For example, the script
subst {abc,[break],def}
returns "abc,", not "abc,,def" and the script
subst {abc,[continue;expr {1+2}],def}
returns "abc,,def", not "abc,3,def".
Other exceptional return codes substitute the returned value
subst {abc,[return foo;expr {1+2}],def}
returns "abc,foo,def", not "abc,3,def" and
subst {abc,[return -code 10 foo;expr {1+2}],def}
also returns "abc,foo,def", not "abc,3,def".
SEE ALSO
Tcl(n), eval(n), break(n), continue(n)
KEYWORDS
backslash substitution, command substitution, variable substitution
Tcl 7.4 subst(n)