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What is first line in shell script?
The first line tells the shell that if you execute the script directly (./run.sh; as opposed to /bin/sh run.sh), it should use that program (/bin/sh in this case) to interpret it. You can also use it to pass arguments, commonly -e (exit on error), or use other programs (/bin/awk, /usr/bin/perl, etc).
What is the first line in the script file?
shebang
The first line of the script is important. It is a special construct, called a shebang, given to the system indicating what program is to be used to interpret the script. In this case, /bin/bash . Other scripting languages such as Perl, awk, tcl, Tk, and python also use this mechanism.
Which is the first line in a script?
The first line called a hashbang or shebang. It tells Unix that this script should be run through the /bin/bash shell. Second line is just the echo statement, which prints the words after it to the terminal.
Why do you put # at the beginning of a script?
Plus, # is a comment in most languages, so the line gets ignored in the subsequent execution. The operating system takes default shell to run your shell script. so mentioning shell path at the beginning of script, you are asking the OS to use that particular shell. It is also useful for portability.
Why do you need to put Bash at the beginning of a script?
The operating system takes default shell to run your shell script. so mentioning shell path at the beginning of script, you are asking the OS to use that particular shell. It is also useful for portability. Every distribution has a default shell. Bash is the default on the majority of the systems.
What is the function of a shell script?
“A shell script is a computer program designed to be run by the Unix shell, a command-line interpreter. The various dialects of shell scripts are considered to be scripting languages. Typical operations performed by shell scripts include file manipulation, program execution, and printing text.”