Simpler bash commands for linux PBA

monkey/infection_monkey/utils/linux/shell_startup_files_modification.py

@@ -3,14 +3,11 @@ BASH_STARTUP_FILES = ["~/.bashrc", "~/.profile", "~/.bash_profile"]
 
 def get_linux_commands_to_modify_shell_startup_files():
     return [
-        'if [ -f {0} ] ;',  # does the file exist?
-        'then',
-        'echo \"# Succesfully modified {0}\" |',
-        'tee -a',
-        '{0}',  # add comment to file
+        'echo \"# Succesfully modified {0}\"',
+        '3<{0} 3<&- |',  # check for existence of file
+        'tee -a',  # append to file
+        '{0}',
         '&&',
-        'sed -i \'$d\' {0} ;',  # remove last line of file
-        'else',
-        'echo \"{0} does not exist\" ; fi'  # mention if file does not exist
+        'sed -i \'$d\' {0}',  # remove last line of file
     ],\
     BASH_STARTUP_FILES