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--- docs:bash:bash_loop [2007/05/14 11:54] – billh
+++ docs:bash:bash_loop [2010/05/07 11:19] (current) – billh
@@ Line 1: / Line 1: @@
+====== bash loop ======
+===== while read =====
+  * :-) This code WILL work on filenames with spaces
+  * taken from http://www.macgeekery.com/tips/cli/handling_filenames_with_spaces_in_bash
+  * quote //"For splits items on a space, regardless of if they’re quoted (if they’re stored in a variable). However, the read command does not."//<code>
+ls -1L *.tiff | while read file;do
+du -h -d 0 "${file}"
+done
+</code>
+  * another example:<code>
+ls -1L *.tiff | while read file;do
+tiff2pdf -p letter -o "${file}".pdf "${file}"
+done
+</code>
+  * use a file containing a list of filenames for a copy operation:<code>
+cat fileswithnotesbug.txt | while read file;do
+cp "${file}" /cygdrive/n/Receive/CIA/nsf/ClmTest/;
+done
+</code>
+===== for =====
+  * :!: This code will NOT work on filenames with spaces unless the IFS variable is set in bash (see man bash for more details)
+  * note that the symbols used are backticks, not single quotes (backtick is the key left of 1)
+<code>
+for file in `ls -1L`;do
+du -h -d 0 $file
+done
+</code>
+Another example showing how to set up new folders with git repo's:
+<code>
+$ mkdir ~/git
+$ cd ~/git
+$ for i in a b c d
+do
+        mkdir $i
+        cd $i
+        git init
+        echo "module $i" > $i.txt
+        git add $i.txt
+        git commit -m "Initial commit, submodule $i"
+        cd ..
+done
+</code>
+original url: http://www.kernel.org/pub/software/scm/git/docs/user-manual.html#submodules
+===== other notes =====
+  * http://www.linuxquestions.org/questions/showthread.php?t=453181
+<code>
+Props to this post, this is a very elegant solution to weird characters in filenames:
+http://www.macgeekery.com/tips/cli/h...spaces_in_bash
+Code:
+find . -type f -print | while read i; do touch "${i}"; done
+    That will fail if any filenames have leading or trailing spaces or end in a backslash. (Not to mention filenames containing newlines.)
+Quote:
+'for' splits on spaces. Period. Regardless of quoting.
+    It does not split on spaces if there is no space in the value of $IFS.
+Quote:
+'read' does not.
+    It does if more than one variable is given as an argument (and IFS contains a space).
+</code>