csplit: add page (#2571)

pages/linux/csplit.md

@@ -0,0 +1,24 @@
+# csplit
+
+> Split a file into pieces.
+> This generates files named "xx00", "xx01", and so on.
+
+- Split a file at lines 5 and 23:
+
+`csplit {{file}} {{5}} {{23}}`
+
+- Split a file every 5 lines (this will fail if the total number of lines is not divisible by 5):
+
+`csplit {{file}} {{5}} {*}`
+
+- Split a file every 5 lines, ignoring exact-division error:
+
+`csplit -k {{file}} {{5}} {*}`
+
+- Split a file at line 5 and use a custom prefix for the output files:
+
+`csplit {{file}} {{5}} -f {{prefix}}`
+
+- Split a file at a line matching a regular expression:
+
+`csplit {{file}} /{{regex}}/`