Programatically performing the same operation in multiple same-level subfolders - shell

Question

I want to write a shell script that would perform a single operation - pdflatex - on multiple files of the same type in same-level subfolders. Here's a simplified version of the directory structure:
/-|
/a-|
| a1.tex
|
/b-|
| b1.tex
|
/c-|
c1.tex
What I'd like to do is have the script launch from /, and perform pdflatex on all the .tex files without having to manually include all of those subdirs in the actual script file.
The algorithm is simple enough on paper:
Go to directory /
Find all directories matching regex given in script (may also use wildcard expression)
Go down n levels, again following regex as needed
Perform pdflatex on all .tex files in current directory
... But I'm not sure how to implement this in a Unix shell script.
Do shell scripts allow for this kind of operation at all? If so, what would an implementation look like?

Answer 1

find is what you seem to be looking for:
find / -mindepth 1 -maxdepth 1 -type f -exec pdflatex {} \;
This would execute pdflatex on all files in the current directory.
In order to perform the action only for files n levels down, replace 1 with n+1 for both -mindepth and -maxdepth options above.
In order to say that you want to filenames matching *.tex, say
find / -mindepth 1 -maxdepth 1 -type f -name "*.tex" -exec pdflatex {} \;

Answer 2

The only thing I might add from what others have said is a couple of parameters, given the desire as such in the question to turn it into a contrived little program.
pdflatesxdirs
#!/bin/bash
pattern='*.tex'
if [ -z $1 ]; then
pattern="${1}.tex"
fi
maxdepth=' '
if [ ! -z $2 ]; then
maxdepth=" -maxdepth $2 "
fi
# borrowed from #devnull ;)
find / -mindepth 1${maxdepth}-type f -name "$pattern" -exec pdflatex {} \;
Then chmod u+x pdflatexdirs
Now call it as
pdflatexdirs [optional search pattern] [optional maxdepth]
With this script:
The default search pattern here is *.tex
If you want to specify maxdepth, you must also provide a search
When you do provide a search, *.tex is appended to whatever you pass