Don't use #!/bin/sh -- it's useless
UNIX absolute file names will always start with /
Don't quote oldstty state
Its defined in stty.1p line 47, that $(stty -g) will never produce string that will make shell expand arguments
Don't use if ith only 1 command, it's unreadable
Having if with only 1 command in its body is useless and unreadable
I Changed it to stty $oldstty || stty sane
Delete useless quotes
$!, $? and $$ will always be an int type
Dont use && with trap
trap will only return non-zero if signal name is invalid
#!/bin/sh --it's useless UNIX absolute file names will always start with/oldsttystate Its defined instty.1pline 47, that$(stty -g)will never produce string that will make shell expand argumentsifith only 1 command, it's unreadable Havingifwith only 1 command in its body is useless and unreadable I Changed it tostty $oldstty || stty sane$!,$?and$$will always be an int type&&withtraptrap will only return non-zero if signal name is invalid