Differences

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--- commands:builtin:read [2020/06/27 08:35]
thebonsai -e works with -u since 5.1 alpha
+++ commands:builtin:read [2021/03/18 06:46] (current)
jarnos Modification by cfajohnson seems to contain false information. Changing IFS is not needed when no variable is used with read.
@@ Line 15: / Line 15: @@
 <WRAP center round info 90%>
-If no ''<NAME>'' is given, the whole line read (without performing word-splitting!) is assigned to the shell variable [[syntax:shellvars#REPLY|REPLY]]. The following code will strip leading and trailing whitespace from the input:
+If no ''<NAME>'' is given, the whole line read (without performing word-splitting!) is assigned to the shell variable [[syntax:shellvars#REPLY|REPLY]]. Then, ''REPLY'' really contains the line as it was read, without stripping pre- and postfix spaces and other things!
 <code>
 while read -r; do
-  line=$REPLY
+  printf '"%s"\n' "$REPLY"
-  ...
+done <<<"  a line with prefix and postfix space  "
-done < text.txt
 </code>
 </WRAP>
-To preserve leading and trailing whitespace in the result, set IFS to the null string:
-<code>
-while IFS= read -r; do
-  line=$REPLY
-  ...
-done < text.txt
-</code>
-Alternately, you can enclose $REPLY in double quotes and avoid fiddling with IFS altogether:
-<code>
-while read -r; do
-  line="$REPLY"
-  ...
-done < text.txt
-</code>
 If a timeout is given, or if the shell variable [[syntax:shellvars#TMOUT|TMOUT]] is set, it is counted from initially waiting for input until the completion of input (i.e. until the complete line is read). That means the timeout can occur during input, too.