toooki
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Unix diff command to find the minus of two text files
I want to print the content of file 1a that are not present in the file 1b. Both files contain one line of similar pattered text.
Example:
$ cat 1a
1234
3456
4567
$ cat 1b
1234
5566
9999
3456
$ grep -vf 1a 1b
5566
9999
$ grep -vf 1b 1a shows those present in 1a but not in 1b. And it works perfectly, But when the files are big (1000K+ records each), the above diff command hangs. Could you suggest workaround or alternate solution that might work? Thanks you.
Example:
$ cat 1a
1234
3456
4567
$ cat 1b
1234
5566
9999
3456
$ grep -vf 1a 1b
5566
9999
$ grep -vf 1b 1a shows those present in 1a but not in 1b. And it works perfectly, But when the files are big (1000K+ records each), the above diff command hangs. Could you suggest workaround or alternate solution that might work? Thanks you.
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If you want to use "diff" then this one:
diff 1b 1a | grep "^>"
will show the lines of 1a which are not in 1b, preceeded by ">".
This one
diff 1a 1b |grep "^<"
will do the same, but the lines in question will be preceeded by "<".
This will remove the prefix:
diff 1a 1b |awk '/^</ {print $2}'
diff 1b 1a | grep "^>"
will show the lines of 1a which are not in 1b, preceeded by ">".
This one
diff 1a 1b |grep "^<"
will do the same, but the lines in question will be preceeded by "<".
This will remove the prefix:
diff 1a 1b |awk '/^</ {print $2}'
Off topic comment deleted.
Gerwin Jansen
EE Topic Advisor
Gerwin Jansen
EE Topic Advisor
ASKER
Many thanks to all.
sort 1b > 1b.sort
sort 1a | comm -2 -3 - 1b.sort
The above worked for me!
sort 1b > 1b.sort
sort 1a | comm -2 -3 - 1b.sort
The above worked for me!
If we can use other commands, this should work:
perl -lne '@ARGV?$s{$_}++:$s{$_}||pr