True and false (commands) True and false (commands) In Unix-like operating systems, codice_1 and codice_2 are commands whose only function is to always return with a predetermined exit status. Programmers and scripts often use the exit status of a command to assess success (exit status zero) or failure (non-zero) of the command. The codice_1 and codice_2 commands represent the logical values of command success, because "true" returns 0, and "false" returns 1. The commands are usually employed in conditional statements and loops of shell scripts. For example, the following shell script repeats the "echo hello" loop until interrupted: while true do done The commands
Tin can recycled, compared to 52% of aluminium cans. In Europe the recycling rate in 2011 is about 74%. Much can recycling occurs at the smelters, but individual consumers also directly reuse cans in various ways. For instance some people use two tin cans to form a camp or survival stove to cook small meals. Tin is corrosion resistant, but acidic food like fruits and vegetables can corrode the tin layer. Nausea, vomiting, and diarrhea have been reported after ingesting canned food containing 200 mg/kg of tin. A 2002 study showed that 99.5% of 1200 tested cans contained below the UK regulatory