如果声明我写的有问题
var1=`COMMAND | grep <Something>`
if [ -n "$var1" ] && if [[ "$var1" != string ]]; then
.
.
.
fi
我想写if if语句检查:
如果var1不为null 并且如果string(可能是helloword)不在var1中那么就做.
我怎样才能做到这一点？
我有这个代码:
sys.stdout.write("\r [*] Serching for "+FirstName+" AND "+LastName )
sys.stdout.flush()
但是当我把它放在循环中时,我一步一步地将FirstName与对方混合在一起,并将LastName与对方混合在一起.
Searching for TEST_THREE AND EXAMPLE_THREE #First time
Searching for TEST_TWOEE AND EXAMPLE_TWOEE #Next time
你看还有EE的THREE后TWO...
我该如何解决？
我有以下C代码:
#include <stdio.h>
char strA[80] = {"string to be used for demonstration purposes."};
char strB[80];
int main(void){
char *pA; //A pointer to type char
char *pB; //Another pointer to type char
puts(strA); //Show string A
pA = strA; //Point pA to string A
puts(pA); //Show what pA is pointing to
//printf("pA = %s", pA);
pB = strB; //Point pB to string B
putchar('\n'); //Move down one line on the screen
while(*pA != '\0'){
*pB++ = *pA++;
}
*pB = '\0'; …如何使用 sed 用某个字符替换文件中的空行？
我使用了以下命令，但它仍然返回原始输入：
sed 's/^$/>/' filename
原始输入：
ACTCTATCATC
CTACTATCTATCC
CCATCATCTACTC
...
期望的输出：
ACTCTATCATC
>
CTACTATCTATCC
>
CCATCATCTACTC
>
...
谢谢你的帮助
我写了一段代码,我应该从for循环中读取变量:
#include <iostream>
using namespace std;
#define NumOfStudents 100
#define NumOfCourses 15
struct Student{
int stdnum, FieldCode, age;
double average, res[NumOfCourses];
char name[20]; //First and Last name length
};
int main(){
struct Student students[NumOfStudents];
int i;
cout << "\tNAME || STUDENT-NUMBER || FIELD-CODE || AGE";
for(i=0; i<NumOfStudents; i++){
cout << "\nSTUDENT #" << i+1 << ": ";
cin >> students[i].name[20] >> students[i].stdnum >> students[i].FieldCode >> students[i].age;
// cin >> students[i].name[20];
}
}
编辑:输出是:
./st
NAME || STUDENT-NUMBER || FIELD-CODE || …我在c ++编程语言中看到一些建议,比如"不要在struct类型中使用char",
struct Student{
int stdnum, FieldCode, age;
double average, marks, res[NumOfCourses];
char Fname[20], Lname[20], cmp[20];
};
最好使用:
struct Student{
int stdnum, FieldCode, age;
double average, marks, res[NumOfCourses];
string Fname, Lname, cmp;
};
关于此事,欢迎任何其他建议
先感谢您
如何在括号之间提取精确的字符串？
我尝试的是:
echo "test [test1] test" | grep -Po "(?=\[).*?(?=\])"
但输出是:
[test1
它应该是:
test1
更好用grep.
这是我的脚本的一部分：
#!/bin/bash
USAGE(){
echo "Usage: ./`basename $0` <File1> <File2>"
}
if [ "$#" -ne "2" ]; then
USAGE
exit 1
fi
if [ ! -f "$1" ]; then
echo "The file \"$1\" does not exist!"
exit 1
fi
if [ ! -f "$2" ]; then
echo "The file \"$2\" does not exist!"
exit 1
fi
我想检查file1是否不存在打印：
The file "file1" does not exist!
如果file2不存在打印：
The file "file2" does not exist!
如果两者都不存在打印：
The files "file1" and "file2" don't …我有这样的清单：
\n\nl=[u'\\u0634\\u0628\\u06a9\\u0647 \\u0645\\u062d\\u0628\\u0627\\u0646 \\u0627\\u0647\\u0644 \\u0628\\u06cc\\u062a \\u0639\\u0644\\u06cc\\u0647\\u0645 \\u0627\\u0644\\u0633\\u0644\\u0627\\u0645', u'\\u0622\\u062e\\u0631\\u06cc\\u0646 \\u0641\\u0639\\u0627\\u0644\\u06cc\\u062a \\u0647\\u0627 \\u062f\\u0631 \\u0647\\u0627\\u062f\\u06cc \\u0646\\u062a \\u0628\\u0631\\u06af\\u0631\\u0641\\u062a\\u0647 \\u0627\\u0632 \\u0646\\u0627\\u0645 \\u0627\\u0645\\u0627\\u0645 \\u0646\\u0642\\u06cc \\u0639\\u0644\\u06cc\\u0647 \\u0627\\u0644\\u0633\\u0644\\u0627\\u0645', u'\\u0648\\u0631\\u0648\\u062f', u'\\u0622\\u062e\\u0631\\u06cc\\u0646 \\u0622\\u0646\\u0644\\u0627\\u06cc\\u0646 \\u0647\\u0627', u'\\u06a9\\u0627\\u0631\\u0628\\u0631\\u0627\\u0646 \\u0641\\u0639\\u0627\\u0644', u'\\u06af\\u0631\\u0648\\u0647 \\u0647\\u0627\\u06cc \\u0641\\u0639\\u0627\\u0644', u'\\u0645\\u062d\\u0628\\u0648\\u0628\\u062a\\u0631\\u06cc\\u0646 \\u0628\\u0631\\u0686\\u0633\\u0628 \\u0647\\u0627', u'\\u0628\\u0647 \\u067e\\u0627\\u062a\\u0648\\u0642 \\u0627\\u06cc\\u0646\\u062a\\u0631\\u0646\\u062a\\u06cc \\u0645\\u062d\\u0628\\u0627\\u0646 \\u0627\\u0647\\u0644 \\u0628\\u06cc\\u062a \\u0639\\u0644\\u06cc\\u0647\\u0645 \\u0627\\u0644\\u0633\\u0644\\u0627\\u0645 \\u062e\\u0648\\u0634 \\u0622\\u0645\\u062f\\u06cc\\u062f', u'\\u06cc\\u0627 \\u062d\\u0633\\u06cc\\u0646(\\u0639)...\\n\\n\\u0645\\u06cc \\u0628\\u0631\\u0645 \\u06cc\\u06a9 \\u0631\\u0648\\u0632 \\u0627\\u0632 \\u0627\\u0635\\u0644\\u06cc\\u062a\\u0645\\n\\u0622\\u062e\\u0631 \\u0627\\u0632 \\u0639\\u0634\\u0642\\u062a \\u0639\\u0631\\u0627\\u0642\\u06cc \\u0645\\u06cc \\u0634\\u0648\\u0645..', u'#\\u0627\\u0644\\u0644\\u0651\\u0647\\u0640\\u064f\\u0640\\u0640\\u0645\\u0651\\u064e \\u0635\\u064e\\u0640\\u0644\\u0651\\u0650 \\u0639\\u064e\\u0644\\u0640\\u06cc #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0622\\u0644\\u0650 #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0639\\u064e\\u062c\\u0651\\u0650\\u0640\\u0640\\u0644\\u0652 \\u0641\\u0640\\u064e\\u0640\\u064e\\u0631\\u064e\\u062c\\u064e\\u0640\\u0647\\u064f\\u0645 \\n#\\u0627\\u0644\\u0644\\u0651\\u0647\\u0640\\u064f\\u0640\\u0640\\u0645\\u0651\\u064e \\u0635\\u064e\\u0640\\u0644\\u0651\\u0650 \\u0639\\u064e\\u0644\\u0640\\u06cc #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0622\\u0644\\u0650 #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0639\\u064e\\u062c\\u0651\\u0650\\u0640\\u0640\\u0644\\u0652 \\u0641\\u0640\\u064e\\u0640\\u064e\\u0631\\u064e\\u062c\\u064e\\u0640\\u0647\\u064f\\u0645 \\n#\\u0627\\u0644\\u0644\\u0651\\u0647\\u0640\\u064f\\u0640\\u0640\\u0645\\u0651\\u064e \\u0635\\u064e\\u0640\\u0644\\u0651\\u0650 \\u0639\\u064e\\u0644\\u0640\\u06cc #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0622\\u0644\\u0650 #\\u0645\\u064f\\u062d\\u064e\\u0640\\u0640\\u0645\\u0651\\u064e\\u062f \\u0648\\u064e\\u0639\\u064e\\u062c\\u0651\\u0650\\u0640\\u0640\\u0644\\u0652 \\u0641\\u0640\\u064e\\u0640\\u064e\\u0631\\u064e\\u062c\\u064e\\u0640\\u0647\\u064f\\u0645', u'#\\u0627\\u0644\\u0644\\u0651\\u0647\\u0640\\u064f\\u0640\\u0640\\u0645\\u0651\\u064e …我有一个像这样的python脚本:
#!/usr/bin/python
import sys
import requests
if len(sys.argv) < 2:
print 'usage: python %s <file-urls>' % (sys.argv[0])
sys.exit(2)
print '%-15s %20s' % ('URL_PAGE', 'STATUS')
FileName = sys.argv[1]
InputFile = open(FileName)
OK = open('ok.txt', 'w+')
NOK = open('nok.txt', 'w+')
for url in InputFile:
status = requests.get(url).status_code
print '%-15s %15s' % (url.strip(), status)
if status == 200:
OK.write('%-15s %15s' % (url.strip(), status) + '\n')
OK.flush()
else:
NOK.write('%-15s %15s' % (url.strip(), status) + '\n')
NOK.flush()
OK.close()
NOK.close()
当我运行它时,以下错误诅咒:
Traceback (most recent call last): …