How to Call a Function (Defined in Shell Script) in a Perl Script

How can I call a shell function from a Perl script?

You'll need to call that function in the same shell that sources utils.sh, so:

my $dir_name = `source utils.sh; getDir`;
chomp($dir_name);
print $dir_name, "\n";

How can I call a shell command in my Perl script?

How to run a shell script from a Perl program

1. Using system system($command, @arguments);

For example:

system("sh", "script.sh", "--help" );

system("sh script.sh --help");

System will execute the $command with
@arguments and return to your script when finished. You may check $!
for certain errors passed to the OS by the external application. Read
the documentation for system for the nuances of how various
invocations are slightly different.

2. Using exec

This is very similar to the use of system, but it will
terminate your script upon execution. Again, read the documentation
for exec for more.

3. Using backticks or qx//

my $output = `script.sh --option`;

my $output = qx/script.sh --option/;

The backtick operator and it's equivalent qx//, excute the command and options inside the operator and return that commands output to STDOUT when it finishes.

There are also ways to run external applications through creative use of open, but this is advanced use; read the documentation for more.

Source and run shell function within perl regex

The answer was to scrap this whole idea and use a better one..

Lets step back first.. Big Picture:

Goal was to make the script program output an executable shell script of the entire recorded session.

Back to Answers..

The above implementation was supposed to remove all prompts and control characters from the output of script (which is the input examples I gave) and then remove the output of each command (i.e. any line that didn't contain control characters).

Passing the evalPS function to perl to execute proved to be quite redundant and getting bash and perl to expand the parameters correctly was a nightmare..

The Final Solution

Scrapped the perl regex idea and used a combination of subshell and history redirection to grab the commands for the entire script session, while it was running.

The entire implementation looks like this:

# log cmds to script file as they are entered (unbuffered)
# spawn script cmd in subshell and wait for it to finish
wait -n
( 
    history -c
    export HISTFILE="${SCRIPT_FILE}"
    shopt -s histappend
    script -q --timing="${TIME_FILE}" "${REC_FILE}"
    history -a
)
...

Simple and much easier to read! :)

Hope this helps anyone trying to make their own mods to script in the future, cheers!

Is it possible to call a function within qx?

my $result = qx(some-shell-command  @{[ get_value() ]});

# or dereferencing single scalar value 
# (last one from get_value if it returns more than one)
my $result = qx(some-shell-command  ${ \get_value() });

but I would rather use your first option.

Explanation: perl arrays interpolate inside "", qx(), etc.

Above is array reference [] holding result of function, being dereferenced by @{}, and interpolated inside qx().

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