Microsoft DOS comp command

comp commandAbout comp
Availability
Comp syntax
Comp examples

About comp

A simple compare that compares two or more files.

Availability

The comp command is an external command and is available in the below Microsoft operating systems. In early versions of MS-DOS (4.0x and earlier) comp.com was used as the external file. All later versions of Windows that have this command use comp.exe as the external file.

MS-DOS 2.0x -5.x
Windows 2000
Windows XP
Windows Vista
Windows 7
Windows 8
Windows 10

Comp syntax

Compares the contents of two files or sets of files.

COMP [data1] [data2] [/D] [/A] [/L] [/N=number] [/C]

data1 Specifies location and name(s) of first file(s) to compare.
data2 Specifies location and name(s) of second files to compare.
/D Displays differences in decimal format.
/A Displays differences in ASCII characters.
/L Displays line numbers for differences.
/N=number Compares only the first specified number of lines in each file.
/C Disregards case of ASCII letters when comparing files.

To compare sets of files, use wildcards in data1 and data2 parameters.

Comp examples

Note: Unless the /N option is used the comp command only compares the size of the file.

comp file1.txt file2.txt /N=10 /A

Compares file1.txt with file2.txt. In this example, we are using the /A option to display the ASCII characters that the compare has found different. If the /A option is not displayed, the comp command displays the differences in hexadecimal notation. Below is an example of how the comp command may display the comparison in this example.

Compare error at LINE 5
file1 = i
file2 = o
Compare error at LINE 5
file1 = v
file2 = u
Compare error at LINE 5
file1 = e
file2 = r
Compare error at LINE 6
file1 = s
file2 = f
Compare error at LINE 6
file1 = x
file2 = v
Compare error at LINE 6
file1 =
file2 = e
Compare error at LINE 7
file1 =

file2 =
Compare error at LINE 7
file1 =
file2 =

Compare error at LINE 8
file1 =

file2 = s

File1 only has 7 lines

Additional information

  • See our compare definition for further information and related links on this term.