32v 1m test
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TEST(1) UNIX Programmer's Manual TEST(1)
test - condition command
_t_e_s_t evaluates the expression _e_x_p_r, and if its value is true then returns zero exit status; otherwise, a non zero exit status is returned. _t_e_s_t returns a non zero exit if there are no arguments.
The following primitives are used to construct _e_x_p_r.
-r file true if the file exists and is readable.
-w file true if the file exists and is writable.
-f file true if the file exists and is not a directory.
-d file true if the file exists exists and is a directory.
-s file true if the file exists and has a size greater than zero.
-t [ fildes ] true if the open file whose file descriptor number is _f_i_l_d_e_s (1 by default) is associated with a ter- minal device.
-z s1 true if the length of string _s_1 is zero.
-n s1 true if the length of the string _s_1 is nonzero.
s1 = s2 true if the strings _s_1 and _s_2 are equal.
s1 != s2 true if the strings _s_1 and _s_2 are not equal.
s1 true if _s_1 is not the null string.
n1 -eq n2 true if the integers _n_1 and _n_2 are algebraically equal. Any of the comparisons -ne, -gt, -ge, -lt, or -le may be used in place of -eq.
These primaries may be combined with the following opera- tors:
! unary negation operator
-a binary _a_n_d operator
-o binary _o_r operator
( expr ) parentheses for grouping.
-a has higher precedence than -o. Notice that all the opera- tors and flags are separate arguments to _t_e_s_t. Notice also that parentheses are meaningful to the Shell and must be escaped.