A cikin shirye-shiryen C, gudanar da ayyuka tare da muhawara masu mahimmanci yana da mahimmanci. Ka yi tunanin aiwatar da aikin da ke karɓar adadin mahawara masu yawa. Shin hakan ba zai nuna alamar lambar ku ta daidaita da buƙatun aikace-aikacen ba, don haka haɓaka sassauci da aikinta? A yau, za mu nutse cikin irin wannan kyakkyawan fasalin da harshen shirye-shirye C ya bayar - va_list - a cikin wani fasali a cikin ɗakin karatu na stdarg.h da ake amfani da shi don sarrafa irin waɗannan ayyuka.
Menene va_list?
Nau'in bayanai ne a cikin C da aka ayyana a cikin ɗakin karatu na stdarg.h. Ana amfani da nau'in don samun dama ga mahawara masu canji a ayyuka.
Misalin Aiki Da Magani
Matsalar da ake tambaya tana kiran aikin C wanda ke karɓar lambobi daban-daban na gardama. Bari mu ɗauka yanayin lissafin inda muke buƙatar taƙaita duk lambobin shigarwa, amma ƙidayar ba ta ƙayyadaddun ba. Anan akwai yuwuwar mafita ta amfani da va_list:
#include
#include
int sum(int num_args,…){
va_list valist;
int sum = 0;
// fara valist don lamba num_args yawan muhawara
va_start (mai inganci, num_args);
// isa ga duk gardamar da aka ba da izini
don (int i=0; i
Mun bayyana va_list valist;, wanda ke aiki azaman mai nuni ga mahawara masu canzawa. va_start (va_list arg_ptr, prev_param) sai a yi amfani da shi, wanda ya fara fara mu valist kuma ya nuna hujjar farko da rashin sanin matsayinsa. va_arg (va_list arg_ptr, datatype) ana amfani da gaba. va_end(va_list) yana tsaftace ƙwaƙwalwar ajiyar da aka tanada don valist. A ƙarshe, muna amfani da waɗannan ayyuka don zagayawa ta hanyar muhawara, ɗaukar jimlar su, da buga su.
Fahimtar Dakunan karatu
Laburaren stdarg.h muhimmin ɗaukar hoto ne a nan, wanda shine madaidaicin ɗakin karatu na C wanda ke ba da damar ayyuka don karɓar adadin mahawara mara iyaka. Ya hada da iri kamar jerin__ da macros kamar farawa, wata_arg, Da kuma va_arshe wanda ke taimakawa wajen cimma madaidaicin aikin hujja. Ta fahimtar waɗannan ɗakunan karatu da takamaiman ayyukansu, za mu iya zama masu iyawa da sassauƙa a cikin shirye-shiryenmu na C.
A cikin shirye-shirye, kamar a cikin salo, fahimtar tarihi da ainihin salo, launuka, da abubuwan da ke faruwa yana da mahimmanci. Waɗannan ayyukan shirye-shiryen C suna wakiltar yanayin daidaitawa da sassauƙan mafita, kamar a cikin salo, inda abubuwa ke tasowa bisa buƙatun al'umma da ƙayatarwa.
