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--- bash:files:parse_a_line_from_a_file [2021/01/26 16:48] – peter
+++ bash:files:parse_a_line_from_a_file [2021/01/26 16:53] (current) – [Method 1] peter
@@ Line 53: / Line 53: @@
 </code>
+<WRAP info>
+**NOTE:**  The **-f** tests that the file exists.
-===== Only get last temperature record =====
+Other options include:
+  * **-b file**:  Checks if file is a block special file; if yes, then the condition becomes true.    [ -b $file ].
+  * **-c file**:  Checks if file is a character special file; if yes, then the condition becomes true.    [ -c $file ].
+  * **-d file**:  Checks if file is a directory; if yes, then the condition becomes true.     [ -d $file ].
+  * **-e file**:  Checks if file exists; is true even if file is a directory but exists.  [ -e $file ].
+  * **-f file**:  Checks if file is an ordinary file as opposed to a directory or special file; if yes, then the condition becomes true.  [ -f $file ].
+  * **-g file**:  Checks if file has its set group ID (SGID) bit set; if yes, then the condition becomes true.    [ -g $file ].
+  * **-k file**:  Checks if file has its sticky bit set; if yes, then the condition becomes true.     [ -k $file ].
+  * **-p file**:  Checks if file is a named pipe; if yes, then the condition becomes true.    [ -p $file ].
+  * **-r file**:  Checks if file is readable; if yes, then the condition becomes true.    [ -r $file ].
+  * **-t file**:  Checks if file descriptor is open and associated with a terminal; if yes, then the condition becomes true.  [ -t $file ].
+  * **-s file**:  Checks if file has size greater than 0; if yes, then condition becomes true.    [ -s $file ].
+  * **-u file**:  Checks if file has its Set User ID (SUID) bit set; if yes, then the condition becomes true.     [ -u $file ].
+  * **-w file**:  Checks if file is writable; if yes, then the condition becomes true.    [ -w $file ].
+  * **-x file**:  Checks if file is executable; if yes, then the condition becomes true.  [ -x $file ].
+</WRAP>
+----
+===== Only get last temperature record =====
 <code>
 #!/bin/bash
-fil=/home/heyu.log.ttyS0
+fil=/home/temp.log.ttyS0
 if [ -f $fil ]