大约有 6,000 项符合查询结果（耗时：0.0164秒） [XML]
How to write log to file
...
os.Open() must have worked differently in the past, but this works for me:
f, err := os.OpenFile("testlogfile", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)
if err != nil {
log.Fatalf("error opening file: %v", err)
}
def...
What does the “yield” keyword do?
...one, etc. And generators return... well that's where yield comes in:
def f123():
yield 1
yield 2
yield 3
for item in f123():
print item
Instead of yield statements, if you had three return statements in f123() only the first would get executed, and the function would exit. But f1...
Dynamic SQL - EXEC(@SQL) versus EXEC SP_EXECUTESQL(@SQL)
...
EXEC('SELECT * FROM FOO WHERE ID=?', 123) will replace the parameter placeholder "?" with the value 123 and then execute the query, returning a result for SELECT * FROM FOO WHERE ID=123
– Peter Wone
Jun 1 '10 at 23:27
...
sed: print only matching group
...it with a 2nd grep.
# To extract \1 from /xx([0-9]+)yy/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'xx[0-9]+yy' | grep -Eo '[0-9]+'
123
4
# To extract \1 from /a([0-9]+)b/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'a[0-9]+b' | grep -Eo '[0-9]+'
678
9
...
How to create new folder? [duplicate]
...uld create a new folder with folder name as given in the program. Is this possible? If yes, please let me know how.
3 Answe...
Reading and writing environment variables in Python? [duplicate]
...
Try using the os module.
import os
os.environ['DEBUSSY'] = '1'
os.environ['FSDB'] = '1'
# Open child processes via os.system(), popen() or fork() and execv()
someVariable = int(os.environ['DEBUSSY'])
See the Python docs on os.environ...
How do you do a simple “chmod +x” from within python?
...
Use os.stat() to get the current permissions, use | to or the bits together, and use os.chmod() to set the updated permissions.
Example:
import os
import stat
st = os.stat('somefile')
os.chmod('somefile', st.st_mode | stat.S_I...
How can I find the current OS in Python? [duplicate]
...e platform. sys.platform will distinguish between linux, other unixes, and OS X, while os.name is "posix" for all of them.
For much more detailed information, use the platform module. This has cross-platform functions that will give you information on the machine architecture, OS and OS version, ve...
How to get Linux console window width in Python
...
import os
rows, columns = os.popen('stty size', 'r').read().split()
uses the 'stty size' command which according to a thread on the python mailing list is reasonably universal on linux. It opens the 'stty size' command as a file, ...
Pythonic way to check if a file exists? [duplicate]
...
To check if a path is an existing file:
os.path.isfile(path)
Return True if path is an existing
regular file. This follows symbolic
links, so both islink() and
isfile() can be true for the same
path.
...