语法错误 - for loop - bash

Question

我的循环问题。我正在使用bash版本4.1.2。

我的代码如下：

### List of files to process from the File .txt defined before ###
g=`cat ${AA}.txt | wc -l`

### Number of time the loop has to make calculated with the number of using  cores ###
let h=($g/$nproc)

### Loop using $h ###
for i in (( i = 1; i <= ${h}; i++ )); do

### Loop to asign every core a process ###
for j in (( j = 1; j <= ${nproc}; j++ )); do

command lines to process $file

done

### Wait for every started process to finish ###
wait

done

我得到的语法错误是：

/var/spool/torque/mom_priv/jobs/1796866.SC: line 57: syntax error near unexpected token `('
/var/spool/torque/mom_priv/jobs/1796866.SC: line 57: `for i in (( i = 1; i <= h; i++ )); do'

有没有办法为i和j编写循环以使其语法有效？感谢

Answer 1

语法是（例如）：

for (( i = 1; i <= $h; i++ )); do

虽然大多数人会这样写：

for (( i = 0; i < $h; i++ )); do

虽然我们是关于它的：

g=`cat ${AA}.txt | wc -l`

可能写得更好：

g=$(wc -l < "$AA.txt")

$( )符号比`

更容易阅读

我们保存子进程

始终引用包含文件名的变量，它们可能包含嵌入的空格。