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--- bash:built-in_variables [2019/11/29 00:37] – removed peter
+++ bash:built-in_variables [2021/01/26 11:42] (current) – peter
@@ Line 1: / Line 1: @@
+====== BASH - Built-in variables ======
+When doing scripting in the shell there are a few built-in variables that we can used:
+<code>
+$$ = The PID number of the process executing the shell.
+$? = Exit status variable.  Nearly all Linux programs return a 0 error status for true and anything else is false.
+$0 = The name of the command you used to call a program.
+$1 = The first argument on the command line.
+$2 = The second argument on the command line.
+$n = The nth argument on the command line. n = 0-9
+$* = All the arguments on the command line.
+$# = The number of command line arguments.
+</code>