我有一个包含目录名的文件:
my_list.txt:
/tmp
/var/tmp
如果目录名已经存在于文件中,我想在添加目录名之前检入Bash。
我有一个包含目录名的文件:
my_list.txt:
/tmp
/var/tmp
如果目录名已经存在于文件中,我想在添加目录名之前检入Bash。
当前回答
关于以下解决方案:
grep -Fxq "$FILENAME" my_list.txt
如果你想知道(像我一样)-Fxq在通俗英语中是什么意思:
F:影响PATTERN的解释方式(固定字符串而不是正则表达式) x:匹配整行 问:嘘……最小的印刷
从男子档案中可以看出:
-F, --fixed-strings
Interpret PATTERN as a list of fixed strings, separated by newlines, any of which is to be matched.
(-F is specified by POSIX.)
-x, --line-regexp
Select only those matches that exactly match the whole line. (-x is specified by POSIX.)
-q, --quiet, --silent
Quiet; do not write anything to standard output. Exit immediately with zero status if any match is
found, even if an error was detected. Also see the -s or --no-messages option. (-q is specified by
POSIX.)
其他回答
关于以下解决方案:
grep -Fxq "$FILENAME" my_list.txt
如果你想知道(像我一样)-Fxq在通俗英语中是什么意思:
F:影响PATTERN的解释方式(固定字符串而不是正则表达式) x:匹配整行 问:嘘……最小的印刷
从男子档案中可以看出:
-F, --fixed-strings
Interpret PATTERN as a list of fixed strings, separated by newlines, any of which is to be matched.
(-F is specified by POSIX.)
-x, --line-regexp
Select only those matches that exactly match the whole line. (-x is specified by POSIX.)
-q, --quiet, --silent
Quiet; do not write anything to standard output. Exit immediately with zero status if any match is
found, even if an error was detected. Also see the -s or --no-messages option. (-q is specified by
POSIX.)
我的版本使用fgrep
FOUND=`fgrep -c "FOUND" $VALIDATION_FILE`
if [ $FOUND -eq 0 ]; then
echo "Not able to find"
else
echo "able to find"
fi
grep -E "(string)" /path/to/file || echo "no match found"
-E选项使grep使用正则表达式
由于某种原因,@Thomas的解决方案对我不起作用,但我有更长的字符串和特殊字符和空格,所以我只是像这样更改参数:
if grep -Fxq 'string you want to find' "/path/to/file"; then
echo "Found"
else
echo "Not found"
fi
希望它能帮助到别人
如果您只是想检查一行是否存在,则不需要创建文件。例如,
if grep -xq "LINE_TO_BE_MATCHED" FILE_TO_LOOK_IN ; then
# code for if it exists
else
# code for if it does not exist
fi