I need to select certain lines from the log file and also save them to a text file. I tried the following but none of them are working as expected. The file "todel.txt" shows 0 bytes. tail -f ...
If I call some command, for instance an echo I can use the results from that command in several other commands with tee. Example: echo "Hello world!" | tee >(command1) >(command2) ...
I am trying to perform this: locate pg_type.h | cat But this command simply does nothing different than locate pg_type.h What should I change ? I want to perform cat pg_type.h wherever pg_type.h ...
Consider the interactive program interactive. I have to run this program fairly frequently, and each time I run it the first few commands are the same. Obviously, having to type those commands over ...
For some commands, it is possible to specify certain input as either stdin or a command line argument. Specifically, suppose command can take stdin input and a filename as command line argument, and ...
Possible Duplicate: Should I care about unnecessary cats? Both would be functionally equivalent, but when using cat wouldn't it be slower because you have a process first reading the file ...
A lot of command-line utilities can take their input either from a pipe or as a filename argument. For long shell scripts, I find starting the chain off with a cat makes it more readable, especially ...