Some people suggest exporting PATH only in .bash_profile
instead of in .bashrc (for Bash).
The helps but does not resolve the issue of possible duplicated paths in $PATH.
The right way is to check for existence of the path in the $PATH environment variable first,
and add it only when …
Hands on the Python Library pexpect
Tips and Traps¶
The command-line tool of some (e.g., network) applications might be slow to authenticate. If you use pexect to automate such a command-line tool, it is best to wait for sometime after sending password using
child.sendline(passwd). If the authentication has ouput on both success and failure, a smart way is to wait for the success or failure message to come out.
IPython Is the Best Shell
IPython is the Best Shell!
-
Use IPython as much as possible.
- IPython has virtues of both shell and Python.
- You should avoid using shell scripts for complicate tasks any way.
-
If you do want to use a Unix/Linux shell, I'd suggest you stick to Bash unless Linux distributions start …
Python Alternatives to Shell
Change Shell in Mac
You can check the current shell in use by running the following command.
echo $SHELL
However,
notice that echo $SHELL does not report the right shell sometimes.
A more robust way is to use echo $0.
The default shell can be changed using thee comamnd chsh.
For example,
thee following …
Spark Issue: Shell Related
Symptom 1
/bin/sh: hdfs: command not found
Possible Causes of Symptom 1
The command hdfs is not on the search path.
Possible Solutions to Symptom 1
- Use the full path to the command.
- Configure the environment variable
PATHbefore you use the command. - Find other alternatives to the command …