What does xx mean in this while loop syntax?


 
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# 1  
Old 03-24-2015
What does xx mean in this while loop syntax?

I have a shell script which has this while loop line
"while read tblName xx; do..."
I understand how while loop works but don't know what does this xx stands for?
# 2  
Old 03-24-2015
man ksh, yields:
Code:
       read [ -ACprsv ] [ -d delim] [ -n n] [ [ -N n] [ [ -t timeout] [ -u unit] [ vname?prompt ] [ vname ... ]
              The shell input mechanism.  One line is read and is broken up into fields using the characters in IFS as separators.  The escape charac-
              ter,  \,  is used to remove any special meaning for the next character and for line continuation.  The -d option causes the read to con-
              tinue to the first character of delim rather than new-line.  The -n option causes at most n bytes to read rather a full  line  but  will
              return  when  reading  from a slow device as soon as any characters have been read.  The -N option causes exactly n to be read unless an
              end-of-file has been encountered or the read times out because of the -t option.  In raw mode, -r, the \ character is not  treated  spe-
              cially.   The  first  field is assigned to the first vname, the second field to the second vname, etc., with leftover fields assigned to
              the last vname.  When vname has the binary attribute and -n or -N is specified, the bytes that are read are  stored  directly  into  the
              variable.   If  the  -v  is  specified,  then  the value of the first vname will be used as a default value when reading from a terminal
              device.  The -A option causes the variable vname to be unset and each field that is read to be stored  in  successive  elements  of  the
              indexed  array  vname.   The -C option causes the variable vname to be read as a compound variable.  Blanks will be ignored when finding
              the beginning open parenthesis.  The -p option causes the input line to be taken from the input pipe of a process spawned by  the  shell
              using  â&.  If the -s option is present, the input will be saved as a command in the history file.  The option -u can be used to specify
              a one digit file descriptor unit unit to read from.  The file descriptor can be opened with the  exec  special  built-in  command.   The
              default  value of unit n is 0.  The option -t is used to specify a timeout in seconds when reading from a terminal or pipe.  If vname is
              omitted, then REPLY is used as the default vname.  An end-of-file with the -p option causes cleanup for this process so that another can
              be  spawned.   If  the  first  argument contains a ?, the remainder of this word is used as a prompt on standard error when the shell is
              interactive.  The exit status is 0 unless an end-of-file is encountered or read has timed out.

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