exfld — Apollo

10.0;exfld (extract_fields), revision 1.0, 88/01/21
exfld (extract_fields) -- Manipulate fields of data.
usage: exfld {field-list | -t [c]}  output_format [pathname ...]



DESCRIPTION
     exfld manipulates data kept in formatted fields.  It copies data from
     specified fields of the input files to specified places in standard
     output.


ARGUMENTS
     field_spec (required)
               Specify either a field list or a free-format separator as
               follows:

     field_list
               Integer list identifying fields in the input file to be copied.
               Up to 9 input fields are allowed.  You can specify a field by
               the columns in which it occurs or by its starting column and
               length.  For example, 5-10 denotes a field that extends from
               column 5 through column 10, and 3+2 denotes a field that starts
               in column 3 and spans 2 columns.  When specifying more than one
               field, separate the specifications with commas, for example,

               5-10,16,72+8

               Fields can overlap, and need not be in ascending numerical
               order.  Thus

               1-25,10,3

               is a valid field specification.

     -t [c]    Free-format separator specification.  If input fields do not
               fall in certain columns, but rather are separated by some
               character (such as a blank or a comma), describe the fields by
               using -t c, replacing c with the appropriate separator.  A tab
               character is the default for c.

     output_format (required)
               Specify literal string representing output format.  Fields from
               input are referred to as $n (for example, $1, $2, $3, and so
               forth) denoting the order the fields are specified in.  Up to 9
               fields are allowed, plus the argument $0 which refers to the
               whole line.  Place the $n symbol in the output format wherever
               the corresponding field should appear, surrounded by any
               characters desired. For example, an output format specification
               of

               "$2 somewords $1"

               produces an output line such as

               field2 somewords field1


     pathname (optional)
               Specify input file to be manipulated.

               Default if omitted:  read standard input

EXAMPLES
     Specify extraction  and input text from standard input.

     $ exfld 1-5,14-18 "$2 follows $1"
     ABCDE is not DEFGH
     DEFGH follows ABCDE
     *** EOF ***
     $
Museum
