The first line, #!/bin/bash, tells Linux where to find the interpreter. The script should also be executable with chmod +x script.sh, which it appears you did. It is highly likely that you created this file with a windows editor, which will place a <cr><lf> at the end of each line. This is the standard under … Read more
I think first two sentences from wikipedia are clear enough: A scripting language, script language or extension language is a programming language that allows some control of a single or many software application(s). Languages chosen for scripting purposes are often much higher-level than the language used by the host application… In this case, the application … Read more
The default globbing in bash does not include filenames starting with a . (aka hidden files). You can change that with shopt -s dotglob $ ls -a . .. .a .b .c d e f $ ls * d e f $ shopt -s dotglob $ ls * .a .b .c d e f $ … Read more
For security reasons, the shell will not search the current directory (by default) for an executable. You have to be specific, and tell bash that your script is in the current directory (.): $ ./MigrateNshell.sh
In Opera, the script.readyState property cannot be trusted. For example, the readyState “loaded” may be fired before the script runs in Opera 9.64. I performed the same test in Opera 9.64 and Opera 10, with different results. In Opera 9.64, the onreadystatechange handler gets fired twice, once before and once after the script runs. The … Read more
Pipe | any output to: sed G Example: ls | sed G If you man sed you will see G Append’s a newline character followed by the contents of the hold space to the pattern space.
source works for me. # — foo.sql DROP TABLE foo; source bar.sql # — bar.sql CREATE TABLE bar (i INT NOT NULL); $ mysql … < foo.sql Now table foo is gone and bar is created.
Two advantages come to mind: Simplicity: direct access to all wonderful linux tools wc, ls, cat, grep, sed… etc. Why constantly use python’s subprocess module? I’m increasingly fond of using gnu parallel, with which you can execute your bash scripts in parallel. E.g. from the man page, batch create thumbs of all jpgs in directory … Read more
You have to explicitly tell sqlplus to do that, in your script. Basically, there are two statements that you can use: WHENEVER SQLERROR EXIT SQL.SQLCODE WHENEVER OSERROR EXIT For example: WHENEVER SQLERROR EXIT SQL.SQLCODE begin SELECT COLUMN_DOES_NOT_EXIST FROM DUAL; END; / And for OS errors: WHENEVER OSERROR EXIT FAILURE START no_such_file For more information, see … Read more
Here is an example I have found in my snippets. Hopefully it is a little bit more comprehensive. First you need to create a file system watcher and subsequently you subscribe to an event that the watcher is generating. This example listens for “Create” events, but could easily be modified to watch out for “Change”. … Read more