Type:
Class
Shell implements an idiomatic Ruby interface for common UNIX shell commands.
It provides users the ability to execute commands with filters and pipes,
like sh/csh by using native facilities of Ruby.
Examples
Temp file creation
In this example we will create three tmpFile's in three
different folders under the /tmp directory.
sh = Shell.cd("/tmp") # Change to the /tmp directory
sh.mkdir "shell-test-1" unless sh.exists?("shell-test-1")
# make the 'shell-test-1' directory if it doesn't already exist
sh.cd("shell-test-1") # Change to the /tmp/shell-test-1 directory
for dir in ["dir1", "dir3", "dir5"]
if !sh.exists?(dir)
sh.mkdir dir # make dir if it doesnt' already exist
sh.cd(dir) do
# change to the `dir` directory
f = sh.open("tmpFile", "w") # open a new file in write mode
f.print "TEST\n" # write to the file
f.close # close the file handler
end
print sh.pwd # output the process working directory
end
end
Temp file creationg with self
This example is identical to the first, except we're using Shell::CommandProcessor#transact.
Shell::CommandProcessor#transact
executes the given block against self, in this case sh; our Shell object. Within the block we can substitute
sh.cd to cd, because the scope within the block
uses sh already.
sh = Shell.cd("/tmp")
sh.transact do
mkdir "shell-test-1" unless exists?("shell-test-1")
cd("shell-test-1")
for dir in ["dir1", "dir3", "dir5"]
if !exists?(dir)
mkdir dir
cd(dir) do
f = open("tmpFile", "w")
f.print "TEST\n"
f.close
end
print pwd
end
end
end
Pipe /etc/printcap into a file
In this example we will read the operating system file
/etc/printcap, generated by cupsd, and then
output it to a new file relative to the pwd of
sh.
sh = Shell.new
sh.cat("/etc/printcap") | sh.tee("tee1") > "tee2"
(sh.cat < "/etc/printcap") | sh.tee("tee11") > "tee12"
sh.cat("/etc/printcap") | sh.tee("tee1") >> "tee2"
(sh.cat < "/etc/printcap") | sh.tee("tee11") >> "tee12"