The other day, the French woke up to hear that they are no longer to talk about "le drive in," "le jungle," or "le Walkman." Henceforth by MINISTERIAL DECREE, the correct words are "le cine-parc," "le soal," and "la baladeur."

Yet another bureaucratic blow had been dealt to Franglais--the bastard offspring of English and French that enjoys great popularity here but which much offends Gallic purists.

The linguistic war can be traced back at least as far as the French Revolution in 1793, when the use of French was made obligatory in all official documents. What is interesting is the relish with which it is being waged by a Socialist government which, in cultural matters, at least, is turning out to be every bit as nationalistic as De Gaulle himself. In this latest battle, 97 Franglais phrases have been officially proscribed.

The attitude of the French to their language, which was once the favored method of expression for men of education and culture the world over, reflects more general attitudes to foreign influence. The determination to resist what has been described as "American cultural imperialism" cuts across the political spectrum--and is always a vote-catching slogan at election time.

In practice though, while the French may rail against the predominant position of English in the modern world, they also recognize its usefulness. English expressions like "le weekend" or "les blue jeans" have become part of the language because they are simpler than any of the French equivalents.

The habit of throwing odd anglicisms into a conversation has led to a situation in which the original English is often somewhat garbled. In Franglais, "hard" does not mean the opposite of soft--but hard-core pornography. Policemen talk to each other on "talkie-walkies" rather than walkie-talkies. "Le footing" means jogging; "le pressing" is the dry cleaner.

Given this complicated background, it is hardly surprising that the latest batch of forbidden phrases should have been received with high-minded satisfaction by some and open derision by others.

One man with particular reason to be pleased was Alain Fantopie, who, as director of the government-sponsored linguistics institute Franterme, spearheads the drive against Franglais. He explains proudly that the word "baladeur," which combines the sense of music and walking, was his own invention--winning out against such competition as "ambulophone" and "sonambule."

The story of how "le baladeur" came to replace "le Walkman" provides an excellent illustration of the bureaucratic red tape in which the language of Voltaire and Proust has become entangled. After dreaming the word up in January 1982, Fantopie had to shepherd it through a commission of government officials, linguistic experts and interested businessmen.

The advice of the prestigious Academie Francaise was sought, as was that of the government's "High Committee for the French Language." Once everybody had been consulted, and nobody could come up with anything better, "le baladeur" was formally approved by the Ministers of Communication and National Education and published in the official gazette.

This makes use of the word obligatory in official decrees and correspondence, school textbooks, and government bulletins. According to the law on the French language of Dec. 31, 1975, the mass media will theoretically be obliged to follow suit.

In fact, Fantopie does not think that it will be necessary to resort to the blunt instrument of the law to enforce use of "le baladeur." "I am sure it will catch on--but, if after two years, no one uses it, then we can forget it," he says magnanimously.

An informal survey of audio shops in Paris suggested that the word has a long way to go before it becomes generally accepted. The question, "Do you have any baladeurs for sale?" was greeted alternately by ribald laughter and confused stares. One salesman, evidently confusing the word with something else, replied indignantly: "Sir, we are a hi-fi shop."

Fantopie insists that he is not waging war on all foreign words. Expressions like "le hot dog," "le holdup" or "la sangria" have, he says, a perfectly legitimate place in the French language. What troubles him more is the widespread use of English in technology and advertising.

"It's enough to say something in English to make people believe you're being modern and up-to-date. We're in danger of reaching a situation in which French would be reserved for literature and family life while English would be the language of work," he says.

The government shares his concern. The minister for Industry, Jean-Pierre Chevenement, recently announced that he would boycott any conference conducted "in a foreign tongue" on French soil. Last year, the Foreign Trade Ministry provoked cries of "protectionism" from the rest of the Common Market when it insisted that all import papers should be in French.

The minister of Culture, Jack Lang, was reported to have toyed with the idea of setting a quota for the number of American records radio stations or discotheques would be allowed to play. He evidently dropped the idea after a survey showed that many discos would go broke if forced to play more French pop.

Meanwhile, records are being kept at Franterme of even the most minor skirmish between French and its rivals. The latest edition of its magazine, Media and Language, contained a self-congratulatory note saying that French had acquitted itself well at last year's UNESCO conference in Paris. Out of 132 speeches, 40 had been delivered in French--against 49 in English, 20 in Spanish, 15 in Arabic, seven in Russian and one in Chinese.

The magazine singled out for particular praise the Afghan delegate, whose use of French was clearly designed "to express a political distance from the other languages."

Franglais, however, has its defenders. Linda Griffith, an American living in Paris, wrote a long letter to the newspaper Liberation, pointing to the wide use of "Frenglish" on the other side of the Atlantic. Among terms she cited were "chic," "croissant," "hors d'oeuvre" and "filet mignon." And, in an attempt to smooth Gallic sensibilities, she recalled that French was known in America as "the language of love."