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--- linux:basics [2019/04/18 10:19]
mstraub [Regular Expressions]
+++ linux:basics [2019/08/14 11:30]
mstraub [Date & Time]
@@ Line 647: / Line 647: @@
 ''date'' is a versatile tool for formatting dates / times and setting the system time ([[linux:installation#date_timezone|see also]]).
-Get the current system time
+Print the current time in different formats
 <code bash>
-date                      # print current system time (human readable)
+date                      # default - a human readable format
+date --rfc-3339=date      # only the date - similar to ISO 8601
+date --rfc-3339=seconds   # date and time - similar to ISO 8601
+date +%Y-%m-%dT%H%M       # custom format useful for scripts, e.g. 2019-08-14T1129
 </code>
+Convert unix timestamps
+<code bash>
+date -d @1278923870       # print the unix timestamp in a human readable format
+</code>
 ====== Working with Text ======
@@ Line 804: / Line 815: @@
 <code bash>
 sed -E 's#(.*),(.*)#\1;\2#g' #replace a single comma with a semicolon
+</code>
+However, even with extended expressions ''sed'' does not support non-greedy expressions as it is possible with PCRE (perl compatible regular expressions). A good resort is to simply use ''perl'' itself:
+<code bash>
+perl -pe 's/.*thevalue="(.*?)".*/\1/g' file.txt
 </code>

Small heaps of code