Use utility file, sample usage: $ file /bin/bash /bin/bash: Mach-O universal binary with 2 architectures /bin/bash (for architecture x86_64): Mach-O 64-bit executable x86_64 /bin/bash (for architecture i386): Mach-O executable i386 $ file /etc/passwd /etc/passwd: ASCII English text $ file code.c code.c: ASCII c program text file manual page
You can use command substitution as: new_filename=$(echo “$a” | sed ‘s/.txt/.log/’) or the less recommended backtick way: new_filename=`echo “$a” | sed ‘s/.txt/.log/’`
You may want to simply switch between character mode and line mode while using the terminal. C-c C-j will run term-line-mode, which treats the terminal buffer more like a normal text-buffer in which you can move the cursor and yank text. You can switch back to character mode by running term-char-mode with C-c C-k.
Recommended reading: The UNIX FAQ: Why do some scripts start with #! … ? The #! magic, details about the shebang/hash-bang mechanism on various Unix flavours Wikipedia: Shebang The unix kernel’s program loader is responsible for doing this. When exec() is called, it asks the kernel to load the program from the file at its … Read more
I would do something like the following (partially motivated by what Roman suggested): make your LaTeX file be \documentclass{article} \begin{document} \input{scriptoutput.tex} \end{document} and generate the file scriptoutput.tex using /usr/local/bin/my-shell-script.sh > scriptoutput.tex You could encode this in a makefile if you want to have it run automatically when necessary. Alternatively, you could use the TeX \write18 … Read more
Under a *NIX, you can use curl to issue a simple HEAD request (HEAD only asks for the headers, not the page body): curl –head http://myurl/ Then you can take only the first line, which contains the HTTP status code (200 OK, 404 Not Found, etc.): curl -s –head http://myurl/ | head -n 1 And … Read more
The best way to do this is using the $SECONDS variable, which has a count of the time that the script (or shell) has been running for. The below sample shows how to run a while loop for 3 seconds. #! /bin/bash end=$((SECONDS+3)) while [ $SECONDS -lt $end ]; do # Do what you want. … Read more
I eventually went with this, which apparently works. I tried the export method at first, but then found that I needed to export every global (constant) variable the script uses. Disable set -e, then run the function call inside a subshell that has set -e enabled. Save the exit status of the subshell in a … Read more
The following command works on recent versions of GNU date: date -d ‘1 hour ago’ “+%m/%d/%Y -%H:%M:%S”
What about this trick… ls -lrt -d -1 $PWD/{*,.*} OR ls -lrt -d -1 $PWD/* I think this has problems with empty directories but if another poster has a tweak I’ll update my answer. Also, you may already know this but this is probably be a good candidate for an alias given it’s lengthiness. [update] … Read more