Shell equality operators (=, ==, -eq) Asked 12 years ago Modified 3 years, 6 months ago Viewed 649k times

Shell - "Shell" is a program, which facilitates the interaction between the user and the operating system (kernel). There are many shell implementations available, like sh, Bash, C shell, Z …

Feb 20, 2011 · When going through one shell script, I saw the term "$?". What is the significance of this term?

Nov 15, 2010 · A bashism is a shell feature which is only supported in bash and certain other more advanced shells. It will not work under busybox sh or dash (which is /bin/sh on a lot of …

BTW, in bash a semi-colon is a statement separator, not a statement terminator, which is a new-line. So if you only have one statement on a line then the ; at end-of-line are superfluous. Not …

The shell is the program which actually processes commands and returns output. Most shells also manage foreground and background processes, command history and command line editing.

I often come across $?, $0, $1, $2, etc in shell scripting. I know that $? returns the exit status of the last command: echo "this will return 0" echo $? But what do the others do? …

I am writing a shell script to run under the KornShell (ksh) on AIX. I would like to use the mkdir command to create a directory. But the directory may already exist, in which case I do not …

I want to redirect both standard output and standard error of a process to a single file. How do I do that in Bash?

May 18, 2010 · Special shell variables verbose If set, causes the words of each command to be printed, after history substitution (if any). Set by the -v command line option. echo If set, each …