True and false (commands) Bash: 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
Genetically modified food controversies basis before introduction. Nonetheless, members of the public are much less likely than scientists to perceive GM foods as safe. The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation. Consumer concerns about food quality first became prominent long before the advent of GM foods in the 1990s. Upton Sinclair's novel "The Jungle" led to the 1906 Pure Food and Drug Act, the first major US legislation on the subject. This began an enduring concern over the purity and later "naturalness" of