I would like to replace the expression "Park-144201" by "Park144201" in a long text file. How to perform it using `sed?
If you want to apply sed to a file to edit just your expression, you could use
sed -i 's/Park-144201/Park144201/g' your_file.txt
Related
I have a file with a string log.txt and inside the file i have multiple lines
line 1 text
line2/random/string/version:0.0.30
line 3 randome stuff
http://someurl:8550/
So currently I use sed to find and replace 0.0.30 to a new value like 0.0.31
with
sed -i s/0.0.30/0.0.31/g log.txt
The problem with this is I need to know the previous value.
Is there a way to always remove 0.0.30 from the string in the file and replace it with a new value ?
Maybe a indexof or a substring.
You can use a regex definition to match 0.0.30 and replace it with 0.0.31 as below. The --posix flag is to ensure no GNU dialects are applied and plain BRE (Basic Regular Expressions) library is used. Since \{2\} is a BRE syntax to match 2 occurrences of the digit.
sed -i --posix 's/[[:digit:]]\.[[:digit:]]\.[[:digit:]]\{2\}/0.0.31/' file
See explanation for regex here.
I want to replace ignore_broadcast_ssid=1 with ignore_broadcast_ssid=0
inside the file /var/run/hostapd-phy0.conf.
This would be my first guess:
sed 's/ignore_broadcast_ssid=1/ignore_broadcast_ssid=0/g' /var/run/hostapd-phy0.conf
But this replaces this option globally, How can I only replace this in one of the sections, starting with bss=wlan0-2 inside the file?
...
bss=wlan0-2
ctrl_interface=/var/run/hostapd
ap_isolate=1
disassoc_low_ack=1
preamble=1
wmm_enabled=1
ignore_broadcast_ssid=0
uapsd_advertisement_enabled=1
auth_algs=1
wpa=0
ssid=temp_wifi
bridge=br-client
bssid=a0:f3:c1:d8:b7:7c
interface=client0
ctrl_interface=/var/run/hostapd
ap_isolate=1
disassoc_low_ack=1
preamble=1
wmm_enabled=1
...
You can first find out the line number of the first text as the starting search index:
grep -n "bss=wlan0-2"
Let assume it is at Line 10. Then apply your sed command at follow:
sed '10s/ignore_broadcast_ssid=1/ignore_broadcast_ssid=0/' /var/run/hostapd-phy0.conf
Make sure you don't have the keyword g at the end of the command as it indicates to replace the matching pattern globally.
sed '/bss=wlan0-2/,/ignore_broadcast_ssid/{s/ignore_broadcast_ssid=1/ignore_broadcast_ssid=0/}' file
Consider the following lines:
prefix1.value[TAB]someString
prefix2.anotherVal[TAB]anotherString
val[TAB]String
pref.stuff[TAB]stuff
dontTouch[TAB]stuff
I would like to have the result
value[TAB]someString
anotherVal[TAB]anotherString
val[TAB]String
stuff[TAB]stuff
dontTouch[TAB]stuff
So I want to cut the prefix. if there is one. Regular expressions work in the way that the first match is the longest so I was not able to create a working program. Is it possible to do this task with a single sed program?
My solution that is not working as it should:
sed 's/^[^\t\.]*\.\?\([^\t\.]\+\)\t\(.*\)/\1\t\2/'
This matches the prefix alone, and replaces it by an empty string.
sed 's/^[^\t\.]*\.//'
Try this if there is only one dot possibe:
sed -e 's/^.*\.//' file
if until first dot
sed 's/^[^.]*\.//' YourFile
if until last dot
se 's/.*\.//' YourFile
up to you to define your prefixe type
Is it possible to use sed to replace some text based on the matching of a condition at the beginning of the text... For example, for the following file, I only want to replace the word 'guest' to 'unwanted-guest' only for the line that begins with the pattern '
541ce0a0c3b4f843ec000001' which is a variable.
541ce0a0c3b4f843ec000001:x:1000:1000:OpenShift guest:/var/lib/openshift/541ce0a0c3b4f843ec000001:/usr/bin/oo-trap-user
541ce468c3b4f843ec000029:x:1001:1001:OpenShift guest:/var/lib/openshift/541ce468c3b4f843ec000029:/usr/bin/oo-trap-user
Try:
sed '/^541ce0a0c3b4f843ec000001/ s/guest/unwanted-guest/'
We have placed a condition in front of the usual sed substitute command. The condition is:
/^541ce0a0c3b4f843ec000001/
This condition limits sed to considering only lines that start with 541ce0a0c3b4f843ec000001 (The caret ^ means must-be-at-the-beginning-of-a-line). The substitute command is:
s/guest/unwanted-guest/
This replaces the first occurrence of guest on the line with unwanted-guest.
Example
Applying this command to your sample input (placed in a file named file):
$ sed '/^541ce0a0c3b4f843ec000001/ s/guest/unwanted-guest/' file
541ce0a0c3b4f843ec000001:x:1000:1000:OpenShift unwanted-guest:/var/lib/openshift/541ce0a0c3b4f843ec000001:/usr/bin/oo-trap-user
541ce468c3b4f843ec000029:x:1001:1001:OpenShift guest:/var/lib/openshift/541ce468c3b4f843ec000029:/usr/bin/oo-trap-user
Using with a variable
$ id=541ce0a0c3b4f843ec000001
$ sed "/^$id/ s/guest/unwanted-guest/" file
541ce0a0c3b4f843ec000001:x:1000:1000:OpenShift unwanted-guest:/var/lib/openshift/541ce0a0c3b4f843ec000001:/usr/bin/oo-trap-user
541ce468c3b4f843ec000029:x:1001:1001:OpenShift guest:/var/lib/openshift/541ce468c3b4f843ec000029:/usr/bin/oo-trap-user
How can I replace a word at a line which begins with a specific pattern on FreeBSD?
Consider the following file contents:
this is to test
that was for test
I want to replace "test" at the line which begins with "this".
In order to perform a replacement for lines starting with this, say:
$ sed '/^this/ s/test/something/' inputfile
this is to something
that was for test
This would replace the word test with something on lines starting with this.
If you want to replace all instances of test on the matching lines, supply the g option to sed:
sed '/^this/ s/test/something/g' inputfile
To make the changes in-place, use the below command:
sed -i '/^this/ s/test/something/g' inputfile;