Oct 11, 2017 · The ./ notation is useful when trying to run a script or other executable in the current directory. Unlike the Windows command prompt, Unix (and Unix-like systems like …

Feb 20, 2011 · Cjm's answer is correct, but $? can be used in silly ways in shell scripts, and I'd like to warn against that. A lot of bad shell scripts have a repeated pattern of code:

It often happens that I want to apply an operation recursively. Some commands, such as grep, use a lowercase r to indicate recursion. For example grep -r foo . Other commands seem to …

As per bash - The Set Builtin manual, if -e/errexit is set, the shell exits immediately if a pipeline consisting of a single simple command, a list or a compound command returns a non-zero status.

May 31, 2012 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

I can't think of a reason why cat < file would ever be better than cat file.However, there are some cases where there is a difference -- for example, grep string file is different from grep string < …

The cat <<EOF syntax is very useful when working with multi-line text in Bash, eg. when assigning multi-line string to a shell variable, file or a pipe.

May 1, 2017 · kill is a utility program, found in Unix-like operating systems, for sending different signals to one or more processes (usually, for terminating, pausing, continuing, etc. – …

Dec 13, 2011 · I'm trying to use the cp command and force an overwrite. I have tried cp -rf /foo/* /bar, but I am still prompted to confirm each overwrite.

Oct 6, 2009 · Linux version 2.6.18.2-34-default (geeko@buildhost) (gcc version 4.1.2 20061115 (prerelease) (SUSE Linux)) #1 SMP Mon Nov 27 11:46:27 UTC 2006 The file peptides.txt …