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Urgent - Command line arguments

hi,
Lets say i have a command line argument like this :
add -this -add
now , i understand that
argv[0] = add
argv[1]= -this
argv[2]= -add

my problem is that i need to count the strlen of argv[1] without minus
i thought the answer was like this : strlen(argv[1] - 1) /* i minus one because i took total of -this which is 5-1) but i found out this is wrong...

the right way to do it is :

strlen(argv[1]+1) /*Why plus one*/
or strlen(&argv[1][1]) /*I thought , this would only give strlen 1 coz argv[1][1] = refers to t...

thanks a lot

slyong

You might mean:

strlen(argv[1])-1 /* the length of "-this" (which is 5) minus 1 gives 4

For the rest, strlen() takes a pointer as the argument and count until it arrives at a null character. So:

strlen(argv[1]+1) points to the 't' of "-this" argv[1] is a pointer to '-' in "-this".. so this will count from 't' until the end which is basically the length of "this".

strlen(&argv[1][1]), argv[1][1] is the character 't', & operator gives you the memory address to it. So again, strlen counts from the memory address of 't' until it meets a null character, which is basically the end of "this".

zizi21

ASKER

I am a bit confused....
I thought strlen doesn't count NULL character...

ASKER CERTIFIED SOLUTION

slyong

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