some more questions about argv

[Momo]

so if i want to see like if argv[1] is starts with a hyphen (-), do i go like
if (strncmp(argv[1], "-",1)==0)
is this correct to check of argv[1] begins wif a hyphen??
or is there something special for the hyphen
any help will be good

 

[Keith Thompson]

so if i want to see like if argv[1] is starts with a hyphen (-), do
i go like
if (strncmp(argv[1], "-",1)==0)
is this correct to check of argv[1] begins wif a hyphen??
or is there something special for the hyphen

Yes, that will work (and no, there's nothing special about hyphen,
it's just another character).

Since you're specifically checking for a single character you can also do:

if (argv[1][0] == '-')

First, of course, you need to check the value of argc to make sure
that argv[1] exists.

You might also be able to use system-supplied argument parsing
routines. The C standard doesn't define any such routines, but you
can see whether your system provides "getopt" or something similar.

 

[Al Bowers]

so if i want to see like if argv[1] is starts with a hyphen (-), do i go like
if (strncmp(argv[1], "-",1)==0)
is this correct to check of argv[1] begins wif a hyphen??
or is there something special for the hyphen
any help will be good

if(argv[1][0] == '-')

or

if(*argv[1] == '-')