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--- linux:misc [2025/10/07 15:20] – [Manipulating Strings] tmade
+++ linux:misc [2026/06/12 11:07] (current) – [Set variable] tmade
@@ Line 35: / Line 35: @@
 }
 </code>
+====yq====
+yq - commandline YAML processor, to visualize yaml output in a readable way
+Example to replace a openshift-route with yq:
+  oc get route/${route} -o yaml | yq eval '.spec.tls.certificate = strenv(TLSCERT) | .spec.tls.key = strenv(TLSKEY)' - | oc replace -f -
 ====Manipulating Strings====
@@ Line 45: / Line 52: @@
 Ueb="String1_String2_String3"
-Ersten wegnehmen:
+Remove 1. string:
 Ueb1=${Ueb#*_}
+# echo $Ueb1
 String2_String3
-Ersten behalten:
+Keep 1. string:
 Ueb1=${Ueb%%_*}
+# echo $Ueb1
 String1
-Letzten wegnehmen:
+Remove last string:
 Ueb1=${Ueb%_*}
+# echo $Ueb1
 String1_String2
-Letzten behalten:
+Keep last string:
 Ueb1=${Ueb##*_}
+# echo $Ueb1
 String3
 </code>
+Another example:
+<code>
+# echo ${TEST:-Foo}      #if "TEST" is empty you are getting default value
+Foo
+# echo $TEST
+# echo ${TEST:=Foo}      #if "TEST" is empty it will be set
+Foo
+# echo $TEST
+Foo
+</code>
+====Set variable====
+Alternative to "sed":
+  var="oldvalue"
+  var="${var/oldvalue/newvalue}"
+  echo $var
+  newvalue
+====awk====
+Examples:
+<code>
+# echo "somestring.or.url.com somestring1.or.url1.com" | awk '{print $1".to.add.anotherstring "$2".and.one.more"}'
+somestring.or.url.com.to.add.anotherstring somestring1.or.url1.com.and.one.more
+</code>
+  awk -F: /my-user/'{print $3}' /etc/passwd                                                                      #getting uid of user "my-user"
+  java -version 2>&1 | awk -F '-' 'NR==2 {print $2}'                                                             #searching for "-" in string and cut all in between, but just from line 2 (NR==2) as the result has 3 lines
+  ifconfig -a | awk '/inet 10/{print $2}'                                                                        #getting IP adress starting with "inet 10"
+  echo "somestring1 somestring2" | awk '{print $1,$2}'
+  awk -F ':' '{print $1 "\t" $4}' /etc/passwd                                                                    #print all username + uid
+  awk 'length($0) > 18' marks.txt                                                                                #print only those lines that contain more than 18 characters