Sep 14, 2012 · In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance, ./myprogram &; echo $! will return the PID of the process …

530 = and == are for string comparisons -eq is for numeric comparisons -eq is in the same family as -lt, -le, -gt, -ge, and -ne == is specific to bash (not present in sh (Bourne shell), ...). Using …

What is the operator =~ called? I'm not sure it has a name. The bash documentation just calls it the =~ operator. Is it only used to compare the right side against the left side? The right side is …

Jan 27, 2017 · I realize you said “read the bash man pages” but at first, I thought you meant read the man pages within bash. At any rate, man bash returns a huge file, which is 4139 lines (72 …

Sep 27, 2015 · What's the difference between <<, <<< and < < in bash?Here document << is known as here-document structure. You let the program know what will be the ending text, and …

Modern shells such as Bash and Zsh have inherited this construct from Ksh, but it is not part of the POSIX specification. If you're in an environment where you have to be strictly POSIX …

Feb 10, 2010 · How do I compare a variable to a string (and do something if they match)?

Jul 17, 2013 · It doesn't mean anything "in bash". [ runs a command called test. -ne is an argument to the test command, not to bash, and you can find its documentation in man test.

#!/bin/bash # To focus exclusively on the performance of each type of increment # statement, we should exclude bash performing while loops from the # performance measure.

123 I have as bash shell script with header #!/bin/bash -e. When I run the script, it will be interrupted after the grep command runs, but when I remove the parameter -e, then the script …