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hi could anyone please tell me in detail about the parameters to the main function argc and argv.please let me know as much as possible.

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covered the basic shape and pointed to a FAQ. The notes below fill common gaps that often matter later: how the argv array is terminated, the lifetime and mutability of its strings, robust parsing patterns, and portable Unicode/Windows behavior.

The argv array itself is terminated by a null pointer (argv[argc] == NULL), and each argv[i] is a standard NUL-terminated C string. That allows iteration without relying on argc directly:

for (char **p = argv; *p != NULL; ++p) {
    puts(*p);
}

Runtime ownership and mutability: the C runtime provides those pointers; do not free them. Modifying argv contents in-place sometimes works on Unix but is not guaranteed portable. When an argument must be altered or retained, copy it into owned storage first:

char *copy = malloc(strlen(argv[1]) + 1);
if (copy) {
    strcpy(copy, argv[1]);
    /* use copy, then free(copy) */
}

Parsing and portability tips: use conversion functions with checks (strtol/strtod with endptr and errno) rather than naive atoi/atof. Example pattern:

char *end;
errno = 0;
long val = strtol(argv[1], &end, 10);
if (end == argv[1] || *end != '\0' || errno == ERANGE) {
    /* handle invalid or out-of-range input */
}

For options use a standard parser (getopt/getopt_long on POSIX or a library). On Windows, consider the wide-argument entry point or CommandLineToArgvW for true Unicode; CRT-provided argv may be ANSI-converted. In short: validate and copy arguments before use, prefer well-tested parsing helpers for options and numbers, and don’t assume argv[0] or the encoding gives a canonical executable path.

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Member Avatar for Rashakil Fol 
int main(int argc, char *argv[])

You can name them whatever you want, but these are the normal names.

argc is non-negative. It gives the number of useful elements in argv.

If argc is positive, argv[0] contains the program name. Then argv[1] through argv[argc - 1] point to character arrays that contain the program's command line arguments.

For example, if I run a program at the command line, such as
unzip filename.zip,

argc will equal 2; and argv[0] will compare equal to "unzip"; and argv[1] will compare equal to "filename.zip".

When I open up a BASH shell and run perl -e 'print "Hello, world!\n"', perl gets an argc of 3, with argv[0] pointing to "perl", argv[1] pointing to "-e", and argv[2] pointing to the string containing

print "Hello, world!\n"

(to represent that string in C syntax, that would be "print \"Hello, world!\\n\"")

Different command line shells use different ways of quoting arguments -- most separate arguments by spaces, with either single or double quotes used to allow arguments with spaces, as seen in the perl example -- this is all invisible to the program, though. In Windows I'd have to write, perl -e "print \"Hello, world!\n\""

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