test [shell]

test expression

or, alternatively and equivalently

[ expression ]

• -s file
  true if file exists and is not empty
• -f file
  true if file is an ordinary file
• -d file
  true if file is a directory
• -r file
  true if file is readable
• -w file
  true if file is writable
• -x file
  true if file is executable
• $X -eq $Y
  true if integer X equals integer Y
• $X -ne $Y
  true if integer X not equal to integer Y
• $X -lt $Y
  true if integer X less than Y
• $X -gt $Y
  true if integer X greater than integer Y
• $X -le $Y
  true if integer X less than or equal to integer Y
• $X -ge $Y
  true if integer X greater than or equal to integer Y
• "$A" = "$B"
  true if string A equals string B
• "$A" != "$B"
  true if string A not equal to string B
• $X ! -gt $Y
  true if integer X is not greater than integer Y
• $E -a $F
  true if expressions E and F are both true
• $E -o $F
  true if either expression E or expression F is true