What does this bash syntax means? ETL_PORT="${ETL_PORT:-6090}"
50136
Using "${a:-b}" for variable assignment in scripts
92375
What does the "L" mean at the end of an integer literal?
23092
What does "$$" mean in the shell?
30195
What's the difference between [ and [[ in Bash?
97476
What does the pipe operator do in SQL?
70911
What does env x='() { :;}; command' bash do and why is it insecure?
29812
How do I test if a variable is a number in Bash?
8932
What is the difference between "all", "default" and "eth*" in /proc/sys/net/ipv[46]/conf/?
131823
Why is setting a variable before a command legal in bash?
157005
What does the ampersand indicate in this bash command 1>&2
13826
In Bash scripting, what's the meaning of " $! "?
29625
What does the notation like 8.6e-28 mean? What is the 'e' for?
61814
What is the "eval" command in bash?
153140
What does “” exactly mean in “echo  temp.txt”?
27330
What do the fields in ls -al output mean?
25478
What does ${1+"$@"} mean in a shell script, and how does it differ from "$@"?
8641
Which are the (Bash) shell special parameters/variables?