Some tricks about redirection
Some syntax particularity about this may have important behaviours. There is some little samples about redirections, STDERR , STDOUT , and arguments ordering.
1 - Overwriting or appending?
Symbol > means redirection.
> means send to as a whole completed file, overwriting target if exist (see noclobber bash feature at #3 later).
means send to as a whole completed file, overwriting target if exist (see bash feature at #3 later). >> means send in addition to would append to target if exist.
In any case, the file would be created if they not exist.
2 - The shell command line is order dependent!!
For testing this, we need a simple command which will send something on both outputs:
$ ls -ld /tmp /tnt ls: cannot access /tnt: No such file or directory drwxrwxrwt 118 root root 196608 Jan 7 11:49 /tmp $ ls -ld /tmp /tnt >/dev/null ls: cannot access /tnt: No such file or directory $ ls -ld /tmp /tnt 2>/dev/null drwxrwxrwt 118 root root 196608 Jan 7 11:49 /tmp
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