I have simple bash script:
#!/bin/sh
column=${1:-1}
awk ' {colawk='$column'+2; print $colawk}'
awk '(x=4; print $x)'
But I have received error:
awk: (x=4; print $x)
awk: ^ syntax error
awk: cmd. line:1: (x=4; print $x)
awk: cmd. line:1: ^ unexpected newline or end of string
Why? Code in the previous line works.
An AWK program is a series of pattern action pairs, written as:
condition { action }
where condition is typically an expression and action is a series of commands.
print is not expression but a statement, so it's a syntax error as expected.
Your problem is with using parentheses instead of braces. Try:
awk '{x=4; print $x}'
instead, as in the following transcript:
pax$ echo a b c d e | awk '(x=4; print $x)'
awk: cmd. line:1: (x=4; print $x)
awk: cmd. line:1: ^ syntax error
awk: cmd. line:2: (x=4; print $x)
awk: cmd. line:2: ^ unexpected newline or end of string
pax$ echo a b c d e | awk '{x=4; print $x}'
d
